mirror of
https://github.com/krahets/hello-algo.git
synced 2026-07-12 15:36:05 +00:00
deploy
This commit is contained in:
krahets
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3565,7 +3565,7 @@
|
||||
<h2 id="1131">11.3.1 算法流程<a class="headerlink" href="#1131" title="Permanent link">¶</a></h2>
|
||||
<p>设数组的长度为 <span class="arithmatex">\(n\)</span> ，冒泡排序的步骤如图 11-5 所示。</p>
|
||||
<ol>
|
||||
<li>首先，对 <span class="arithmatex">\(n\)</span> 个元素执行“冒泡”，<strong>将数组的最大元素交换至正确位置</strong>，</li>
|
||||
<li>首先，对 <span class="arithmatex">\(n\)</span> 个元素执行“冒泡”，<strong>将数组的最大元素交换至正确位置</strong>。</li>
|
||||
<li>接下来，对剩余 <span class="arithmatex">\(n - 1\)</span> 个元素执行“冒泡”，<strong>将第二大元素交换至正确位置</strong>。</li>
|
||||
<li>以此类推，经过 <span class="arithmatex">\(n - 1\)</span> 轮“冒泡”后，<strong>前 <span class="arithmatex">\(n - 1\)</span> 大的元素都被交换至正确位置</strong>。</li>
|
||||
<li>仅剩的一个元素必定是最小元素，无须排序，因此数组排序完成。</li>
|
||||
@@ -3804,7 +3804,7 @@
|
||||
<a id="__codelineno-12-11" name="__codelineno-12-11" href="#__codelineno-12-11"></a> <span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">],</span> <span class="n">nums</span><span class="p">[</span><span class="n">j</span> <span class="o">+</span> <span class="mi">1</span><span class="p">]</span> <span class="o">=</span> <span class="n">nums</span><span class="p">[</span><span class="n">j</span> <span class="o">+</span> <span class="mi">1</span><span class="p">],</span> <span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">]</span>
|
||||
<a id="__codelineno-12-12" name="__codelineno-12-12" href="#__codelineno-12-12"></a> <span class="n">flag</span> <span class="o">=</span> <span class="kc">True</span> <span class="c1"># 记录交换元素</span>
|
||||
<a id="__codelineno-12-13" name="__codelineno-12-13" href="#__codelineno-12-13"></a> <span class="k">if</span> <span class="ow">not</span> <span class="n">flag</span><span class="p">:</span>
|
||||
<a id="__codelineno-12-14" name="__codelineno-12-14" href="#__codelineno-12-14"></a> <span class="k">break</span> <span class="c1"># 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-12-14" name="__codelineno-12-14" href="#__codelineno-12-14"></a> <span class="k">break</span> <span class="c1"># 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
@@ -3823,7 +3823,7 @@
|
||||
<a id="__codelineno-13-13" name="__codelineno-13-13" href="#__codelineno-13-13"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-13-14" name="__codelineno-13-14" href="#__codelineno-13-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-13-15" name="__codelineno-13-15" href="#__codelineno-13-15"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span>
|
||||
<a id="__codelineno-13-16" name="__codelineno-13-16" href="#__codelineno-13-16"></a><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-13-16" name="__codelineno-13-16" href="#__codelineno-13-16"></a><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-13-17" name="__codelineno-13-17" href="#__codelineno-13-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-13-18" name="__codelineno-13-18" href="#__codelineno-13-18"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3845,7 +3845,7 @@
|
||||
<a id="__codelineno-14-14" name="__codelineno-14-14" href="#__codelineno-14-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-14-15" name="__codelineno-14-15" href="#__codelineno-14-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-14-16" name="__codelineno-14-16" href="#__codelineno-14-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span>
|
||||
<a id="__codelineno-14-17" name="__codelineno-14-17" href="#__codelineno-14-17"></a><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-14-17" name="__codelineno-14-17" href="#__codelineno-14-17"></a><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-14-18" name="__codelineno-14-18" href="#__codelineno-14-18"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-14-19" name="__codelineno-14-19" href="#__codelineno-14-19"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3864,7 +3864,7 @@
|
||||
<a id="__codelineno-15-11" name="__codelineno-15-11" href="#__codelineno-15-11"></a><span class="w"> </span><span class="n">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">true</span><span class="p">;</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-15-12" name="__codelineno-15-12" href="#__codelineno-15-12"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-15-13" name="__codelineno-15-13" href="#__codelineno-15-13"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-15-14" name="__codelineno-15-14" href="#__codelineno-15-14"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-15-14" name="__codelineno-15-14" href="#__codelineno-15-14"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-15-15" name="__codelineno-15-15" href="#__codelineno-15-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-15-16" name="__codelineno-15-16" href="#__codelineno-15-16"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3883,7 +3883,7 @@
|
||||
<a id="__codelineno-16-11" name="__codelineno-16-11" href="#__codelineno-16-11"></a><span class="w"> </span><span class="nx">flag</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="kc">true</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-16-12" name="__codelineno-16-12" href="#__codelineno-16-12"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-16-13" name="__codelineno-16-13" href="#__codelineno-16-13"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-16-14" name="__codelineno-16-14" href="#__codelineno-16-14"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="nx">flag</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="kc">false</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-16-14" name="__codelineno-16-14" href="#__codelineno-16-14"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="nx">flag</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="kc">false</span><span class="w"> </span><span class="p">{</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-16-15" name="__codelineno-16-15" href="#__codelineno-16-15"></a><span class="w"> </span><span class="k">break</span>
|
||||
<a id="__codelineno-16-16" name="__codelineno-16-16" href="#__codelineno-16-16"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-16-17" name="__codelineno-16-17" href="#__codelineno-16-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
@@ -3905,7 +3905,7 @@
|
||||
<a id="__codelineno-17-12" name="__codelineno-17-12" href="#__codelineno-17-12"></a> <span class="n">flag</span> <span class="p">=</span> <span class="kc">true</span> <span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-17-13" name="__codelineno-17-13" href="#__codelineno-17-13"></a> <span class="p">}</span>
|
||||
<a id="__codelineno-17-14" name="__codelineno-17-14" href="#__codelineno-17-14"></a> <span class="p">}</span>
|
||||
<a id="__codelineno-17-15" name="__codelineno-17-15" href="#__codelineno-17-15"></a> <span class="k">if</span> <span class="o">!</span><span class="n">flag</span> <span class="p">{</span> <span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-17-15" name="__codelineno-17-15" href="#__codelineno-17-15"></a> <span class="k">if</span> <span class="o">!</span><span class="n">flag</span> <span class="p">{</span> <span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-17-16" name="__codelineno-17-16" href="#__codelineno-17-16"></a> <span class="k">break</span>
|
||||
<a id="__codelineno-17-17" name="__codelineno-17-17" href="#__codelineno-17-17"></a> <span class="p">}</span>
|
||||
<a id="__codelineno-17-18" name="__codelineno-17-18" href="#__codelineno-17-18"></a> <span class="p">}</span>
|
||||
@@ -3928,7 +3928,7 @@
|
||||
<a id="__codelineno-18-13" name="__codelineno-18-13" href="#__codelineno-18-13"></a><span class="w"> </span><span class="nx">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kc">true</span><span class="p">;</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-18-14" name="__codelineno-18-14" href="#__codelineno-18-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-18-15" name="__codelineno-18-15" href="#__codelineno-18-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-18-16" name="__codelineno-18-16" href="#__codelineno-18-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="nx">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-18-16" name="__codelineno-18-16" href="#__codelineno-18-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="nx">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-18-17" name="__codelineno-18-17" href="#__codelineno-18-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-18-18" name="__codelineno-18-18" href="#__codelineno-18-18"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3949,7 +3949,7 @@
|
||||
<a id="__codelineno-19-13" name="__codelineno-19-13" href="#__codelineno-19-13"></a><span class="w"> </span><span class="nx">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kc">true</span><span class="p">;</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-19-14" name="__codelineno-19-14" href="#__codelineno-19-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-19-15" name="__codelineno-19-15" href="#__codelineno-19-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-19-16" name="__codelineno-19-16" href="#__codelineno-19-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="nx">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-19-16" name="__codelineno-19-16" href="#__codelineno-19-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="nx">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-19-17" name="__codelineno-19-17" href="#__codelineno-19-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-19-18" name="__codelineno-19-18" href="#__codelineno-19-18"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3970,7 +3970,7 @@
|
||||
<a id="__codelineno-20-13" name="__codelineno-20-13" href="#__codelineno-20-13"></a><span class="w"> </span><span class="n">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kc">true</span><span class="p">;</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-20-14" name="__codelineno-20-14" href="#__codelineno-20-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-20-15" name="__codelineno-20-15" href="#__codelineno-20-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-20-16" name="__codelineno-20-16" href="#__codelineno-20-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-20-16" name="__codelineno-20-16" href="#__codelineno-20-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-20-17" name="__codelineno-20-17" href="#__codelineno-20-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-20-18" name="__codelineno-20-18" href="#__codelineno-20-18"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -3991,7 +3991,7 @@
|
||||
<a id="__codelineno-21-13" name="__codelineno-21-13" href="#__codelineno-21-13"></a><span class="w"> </span><span class="n">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kc">true</span><span class="p">;</span><span class="w"> </span><span class="c1">// 记录交换元素</span>
|
||||
<a id="__codelineno-21-14" name="__codelineno-21-14" href="#__codelineno-21-14"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-21-15" name="__codelineno-21-15" href="#__codelineno-21-15"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-21-16" name="__codelineno-21-16" href="#__codelineno-21-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="o">!</span><span class="n">flag</span><span class="w"> </span><span class="p">{</span><span class="k">break</span><span class="p">};</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-21-16" name="__codelineno-21-16" href="#__codelineno-21-16"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="o">!</span><span class="n">flag</span><span class="w"> </span><span class="p">{</span><span class="k">break</span><span class="p">};</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-21-17" name="__codelineno-21-17" href="#__codelineno-21-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-21-18" name="__codelineno-21-18" href="#__codelineno-21-18"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
@@ -4035,7 +4035,7 @@
|
||||
<a id="__codelineno-23-15" name="__codelineno-23-15" href="#__codelineno-23-15"></a><span class="w"> </span><span class="n">flag</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kc">true</span><span class="p">;</span>
|
||||
<a id="__codelineno-23-16" name="__codelineno-23-16" href="#__codelineno-23-16"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-23-17" name="__codelineno-23-17" href="#__codelineno-23-17"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-23-18" name="__codelineno-23-18" href="#__codelineno-23-18"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮冒泡未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-23-18" name="__codelineno-23-18" href="#__codelineno-23-18"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">flag</span><span class="p">)</span><span class="w"> </span><span class="k">break</span><span class="p">;</span><span class="w"> </span><span class="c1">// 此轮“冒泡”未交换任何元素，直接跳出</span>
|
||||
<a id="__codelineno-23-19" name="__codelineno-23-19" href="#__codelineno-23-19"></a><span class="w"> </span><span class="p">}</span>
|
||||
<a id="__codelineno-23-20" name="__codelineno-23-20" href="#__codelineno-23-20"></a><span class="p">}</span>
|
||||
</code></pre></div>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3901,9 +3901,9 @@
|
||||
<h2 id="1182">11.8.2 算法特性<a class="headerlink" href="#1182" title="Permanent link">¶</a></h2>
|
||||
<p>桶排序适用于处理体量很大的数据。例如，输入数据包含 100 万个元素，由于空间限制，系统内存无法一次性加载所有数据。此时，可以将数据分成 1000 个桶，然后分别对每个桶进行排序，最后将结果合并。</p>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n + k)\)</span></strong> ：假设元素在各个桶内平均分布，那么每个桶内的元素数量为 <span class="arithmatex">\(\frac{n}{k}\)</span> 。假设排序单个桶使用 <span class="arithmatex">\(O(\frac{n}{k} \log\frac{n}{k})\)</span> 时间，则排序所有桶使用 <span class="arithmatex">\(O(n \log\frac{n}{k})\)</span> 时间。<strong>当桶数量 <span class="arithmatex">\(k\)</span> 比较大时，时间复杂度则趋向于 <span class="arithmatex">\(O(n)\)</span></strong> 。合并结果时需要遍历所有桶和元素，花费 <span class="arithmatex">\(O(n + k)\)</span> 时间。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n + k)\)</span></strong> ：假设元素在各个桶内平均分布，那么每个桶内的元素数量为 <span class="arithmatex">\(\frac{n}{k}\)</span> 。假设排序单个桶使用 <span class="arithmatex">\(O(\frac{n}{k} \log\frac{n}{k})\)</span> 时间，则排序所有桶使用 <span class="arithmatex">\(O(n \log\frac{n}{k})\)</span> 时间。<strong>当桶数量 <span class="arithmatex">\(k\)</span> 比较大时，时间复杂度则趋向于 <span class="arithmatex">\(O(n)\)</span></strong> 。合并结果时需要遍历所有桶和元素，花费 <span class="arithmatex">\(O(n + k)\)</span> 时间。</li>
|
||||
<li><strong>自适应排序</strong>：在最差情况下，所有数据被分配到一个桶中，且排序该桶使用 <span class="arithmatex">\(O(n^2)\)</span> 时间。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(n + k)\)</span>、非原地排序</strong>：需要借助 <span class="arithmatex">\(k\)</span> 个桶和总共 <span class="arithmatex">\(n\)</span> 个元素的额外空间。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(n + k)\)</span>、非原地排序</strong>：需要借助 <span class="arithmatex">\(k\)</span> 个桶和总共 <span class="arithmatex">\(n\)</span> 个元素的额外空间。</li>
|
||||
<li>桶排序是否稳定取决于排序桶内元素的算法是否稳定。</li>
|
||||
</ul>
|
||||
<h2 id="1183">11.8.3 如何实现平均分配<a class="headerlink" href="#1183" title="Permanent link">¶</a></h2>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -4281,8 +4281,8 @@
|
||||
</div>
|
||||
<h2 id="1193">11.9.3 算法特性<a class="headerlink" href="#1193" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n + m)\)</span></strong> ：涉及遍历 <code>nums</code> 和遍历 <code>counter</code> ，都使用线性时间。一般情况下 <span class="arithmatex">\(n \gg m\)</span> ，时间复杂度趋于 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(n + m)\)</span>、非原地排序</strong>：借助了长度分别为 <span class="arithmatex">\(n\)</span> 和 <span class="arithmatex">\(m\)</span> 的数组 <code>res</code> 和 <code>counter</code> 。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n + m)\)</span></strong> ：涉及遍历 <code>nums</code> 和遍历 <code>counter</code> ，都使用线性时间。一般情况下 <span class="arithmatex">\(n \gg m\)</span> ，时间复杂度趋于 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(n + m)\)</span>、非原地排序</strong>：借助了长度分别为 <span class="arithmatex">\(n\)</span> 和 <span class="arithmatex">\(m\)</span> 的数组 <code>res</code> 和 <code>counter</code> 。</li>
|
||||
<li><strong>稳定排序</strong>：由于向 <code>res</code> 中填充元素的顺序是“从右向左”的，因此倒序遍历 <code>nums</code> 可以避免改变相等元素之间的相对位置，从而实现稳定排序。实际上，正序遍历 <code>nums</code> 也可以得到正确的排序结果，但结果是非稳定的。</li>
|
||||
</ul>
|
||||
<h2 id="1194">11.9.4 局限性<a class="headerlink" href="#1194" title="Permanent link">¶</a></h2>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -4036,8 +4036,8 @@
|
||||
</div>
|
||||
<h2 id="1172">11.7.2 算法特性<a class="headerlink" href="#1172" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n \log n)\)</span>、非自适应排序</strong>：建堆操作使用 <span class="arithmatex">\(O(n)\)</span> 时间。从堆中提取最大元素的时间复杂度为 <span class="arithmatex">\(O(\log n)\)</span> ，共循环 <span class="arithmatex">\(n - 1\)</span> 轮。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：几个指针变量使用 <span class="arithmatex">\(O(1)\)</span> 空间。元素交换和堆化操作都是在原数组上进行的。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span>、非自适应排序</strong>：建堆操作使用 <span class="arithmatex">\(O(n)\)</span> 时间。从堆中提取最大元素的时间复杂度为 <span class="arithmatex">\(O(\log n)\)</span> ，共循环 <span class="arithmatex">\(n - 1\)</span> 轮。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：几个指针变量使用 <span class="arithmatex">\(O(1)\)</span> 空间。元素交换和堆化操作都是在原数组上进行的。</li>
|
||||
<li><strong>非稳定排序</strong>：在交换堆顶元素和堆底元素时，相等元素的相对位置可能发生变化。</li>
|
||||
</ul>
|
||||
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -2326,7 +2326,7 @@
|
||||
<li class="md-nav__item">
|
||||
<a href="#1143" class="md-nav__link">
|
||||
<span class="md-ellipsis">
|
||||
11.4.3 插入排序优势
|
||||
11.4.3 插入排序的优势
|
||||
</span>
|
||||
</a>
|
||||
|
||||
@@ -3490,7 +3490,7 @@
|
||||
<li class="md-nav__item">
|
||||
<a href="#1143" class="md-nav__link">
|
||||
<span class="md-ellipsis">
|
||||
11.4.3 插入排序优势
|
||||
11.4.3 插入排序的优势
|
||||
</span>
|
||||
</a>
|
||||
|
||||
@@ -3754,11 +3754,11 @@
|
||||
</div>
|
||||
<h2 id="1142">11.4.2 算法特性<a class="headerlink" href="#1142" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n^2)\)</span>、自适应排序</strong>：在最差情况下，每次插入操作分别需要循环 <span class="arithmatex">\(n - 1\)</span>、<span class="arithmatex">\(n-2\)</span>、<span class="arithmatex">\(\dots\)</span>、<span class="arithmatex">\(2\)</span>、<span class="arithmatex">\(1\)</span> 次，求和得到 <span class="arithmatex">\((n - 1) n / 2\)</span> ，因此时间复杂度为 <span class="arithmatex">\(O(n^2)\)</span> 。在遇到有序数据时，插入操作会提前终止。当输入数组完全有序时，插入排序达到最佳时间复杂度 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：指针 <span class="arithmatex">\(i\)</span> 和 <span class="arithmatex">\(j\)</span> 使用常数大小的额外空间。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n^2)\)</span>、自适应排序</strong>：在最差情况下，每次插入操作分别需要循环 <span class="arithmatex">\(n - 1\)</span>、<span class="arithmatex">\(n-2\)</span>、<span class="arithmatex">\(\dots\)</span>、<span class="arithmatex">\(2\)</span>、<span class="arithmatex">\(1\)</span> 次，求和得到 <span class="arithmatex">\((n - 1) n / 2\)</span> ，因此时间复杂度为 <span class="arithmatex">\(O(n^2)\)</span> 。在遇到有序数据时，插入操作会提前终止。当输入数组完全有序时，插入排序达到最佳时间复杂度 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：指针 <span class="arithmatex">\(i\)</span> 和 <span class="arithmatex">\(j\)</span> 使用常数大小的额外空间。</li>
|
||||
<li><strong>稳定排序</strong>：在插入操作过程中，我们会将元素插入到相等元素的右侧，不会改变它们的顺序。</li>
|
||||
</ul>
|
||||
<h2 id="1143">11.4.3 插入排序优势<a class="headerlink" href="#1143" title="Permanent link">¶</a></h2>
|
||||
<h2 id="1143">11.4.3 插入排序的优势<a class="headerlink" href="#1143" title="Permanent link">¶</a></h2>
|
||||
<p>插入排序的时间复杂度为 <span class="arithmatex">\(O(n^2)\)</span> ，而我们即将学习的快速排序的时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span> 。尽管插入排序的时间复杂度更高，<strong>但在数据量较小的情况下，插入排序通常更快</strong>。</p>
|
||||
<p>这个结论与线性查找和二分查找的适用情况的结论类似。快速排序这类 <span class="arithmatex">\(O(n \log n)\)</span> 的算法属于基于分治策略的排序算法，往往包含更多单元计算操作。而在数据量较小时，<span class="arithmatex">\(n^2\)</span> 和 <span class="arithmatex">\(n \log n\)</span> 的数值比较接近，复杂度不占主导地位；每轮中的单元操作数量起到决定性作用。</p>
|
||||
<p>实际上，许多编程语言（例如 Java）的内置排序函数采用了插入排序，大致思路为：对于长数组，采用基于分治策略的排序算法，例如快速排序；对于短数组，直接使用插入排序。</p>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3595,12 +3595,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.py</span><pre><span></span><code><a id="__codelineno-0-1" name="__codelineno-0-1" href="#__codelineno-0-1"></a><span class="k">def</span> <span class="nf">merge</span><span class="p">(</span><span class="n">nums</span><span class="p">:</span> <span class="nb">list</span><span class="p">[</span><span class="nb">int</span><span class="p">],</span> <span class="n">left</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">mid</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">right</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span>
|
||||
<a id="__codelineno-0-2" name="__codelineno-0-2" href="#__codelineno-0-2"></a><span class="w"> </span><span class="sd">"""合并左子数组和右子数组"""</span>
|
||||
<a id="__codelineno-0-3" name="__codelineno-0-3" href="#__codelineno-0-3"></a> <span class="c1"># 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-0-3" name="__codelineno-0-3" href="#__codelineno-0-3"></a> <span class="c1"># 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-0-4" name="__codelineno-0-4" href="#__codelineno-0-4"></a> <span class="c1"># 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-0-5" name="__codelineno-0-5" href="#__codelineno-0-5"></a> <span class="n">tmp</span> <span class="o">=</span> <span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">*</span> <span class="p">(</span><span class="n">right</span> <span class="o">-</span> <span class="n">left</span> <span class="o">+</span> <span class="mi">1</span><span class="p">)</span>
|
||||
<a id="__codelineno-0-6" name="__codelineno-0-6" href="#__codelineno-0-6"></a> <span class="c1"># 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-0-7" name="__codelineno-0-7" href="#__codelineno-0-7"></a> <span class="n">i</span><span class="p">,</span> <span class="n">j</span><span class="p">,</span> <span class="n">k</span> <span class="o">=</span> <span class="n">left</span><span class="p">,</span> <span class="n">mid</span> <span class="o">+</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">0</span>
|
||||
<a id="__codelineno-0-8" name="__codelineno-0-8" href="#__codelineno-0-8"></a> <span class="c1"># 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-0-8" name="__codelineno-0-8" href="#__codelineno-0-8"></a> <span class="c1"># 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-0-9" name="__codelineno-0-9" href="#__codelineno-0-9"></a> <span class="k">while</span> <span class="n">i</span> <span class="o"><=</span> <span class="n">mid</span> <span class="ow">and</span> <span class="n">j</span> <span class="o"><=</span> <span class="n">right</span><span class="p">:</span>
|
||||
<a id="__codelineno-0-10" name="__codelineno-0-10" href="#__codelineno-0-10"></a> <span class="k">if</span> <span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span> <span class="o"><=</span> <span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">]:</span>
|
||||
<a id="__codelineno-0-11" name="__codelineno-0-11" href="#__codelineno-0-11"></a> <span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="o">=</span> <span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span>
|
||||
@@ -3638,12 +3638,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.cpp</span><pre><span></span><code><a id="__codelineno-1-1" name="__codelineno-1-1" href="#__codelineno-1-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-1-2" name="__codelineno-1-2" href="#__codelineno-1-2"></a><span class="kt">void</span><span class="w"> </span><span class="nf">merge</span><span class="p">(</span><span class="n">vector</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="o">&</span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-1-3" name="__codelineno-1-3" href="#__codelineno-1-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-1-3" name="__codelineno-1-3" href="#__codelineno-1-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-1-4" name="__codelineno-1-4" href="#__codelineno-1-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-1-5" name="__codelineno-1-5" href="#__codelineno-1-5"></a><span class="w"> </span><span class="n">vector</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">tmp</span><span class="p">(</span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">);</span>
|
||||
<a id="__codelineno-1-6" name="__codelineno-1-6" href="#__codelineno-1-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-1-7" name="__codelineno-1-7" href="#__codelineno-1-7"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="n">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-1-8" name="__codelineno-1-8" href="#__codelineno-1-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-1-8" name="__codelineno-1-8" href="#__codelineno-1-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-1-9" name="__codelineno-1-9" href="#__codelineno-1-9"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-1-10" name="__codelineno-1-10" href="#__codelineno-1-10"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">])</span>
|
||||
<a id="__codelineno-1-11" name="__codelineno-1-11" href="#__codelineno-1-11"></a><span class="w"> </span><span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -3680,12 +3680,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.java</span><pre><span></span><code><a id="__codelineno-2-1" name="__codelineno-2-1" href="#__codelineno-2-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-2-2" name="__codelineno-2-2" href="#__codelineno-2-2"></a><span class="kt">void</span><span class="w"> </span><span class="nf">merge</span><span class="p">(</span><span class="kt">int</span><span class="o">[]</span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-2-3" name="__codelineno-2-3" href="#__codelineno-2-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-2-3" name="__codelineno-2-3" href="#__codelineno-2-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-2-4" name="__codelineno-2-4" href="#__codelineno-2-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-2-5" name="__codelineno-2-5" href="#__codelineno-2-5"></a><span class="w"> </span><span class="kt">int</span><span class="o">[]</span><span class="w"> </span><span class="n">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">new</span><span class="w"> </span><span class="kt">int</span><span class="o">[</span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="o">]</span><span class="p">;</span>
|
||||
<a id="__codelineno-2-6" name="__codelineno-2-6" href="#__codelineno-2-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-2-7" name="__codelineno-2-7" href="#__codelineno-2-7"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="n">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-2-8" name="__codelineno-2-8" href="#__codelineno-2-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-2-8" name="__codelineno-2-8" href="#__codelineno-2-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-2-9" name="__codelineno-2-9" href="#__codelineno-2-9"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-2-10" name="__codelineno-2-10" href="#__codelineno-2-10"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">nums</span><span class="o">[</span><span class="n">i</span><span class="o">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="o">[</span><span class="n">j</span><span class="o">]</span><span class="p">)</span>
|
||||
<a id="__codelineno-2-11" name="__codelineno-2-11" href="#__codelineno-2-11"></a><span class="w"> </span><span class="n">tmp</span><span class="o">[</span><span class="n">k</span><span class="o">++]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="o">[</span><span class="n">i</span><span class="o">++]</span><span class="p">;</span>
|
||||
@@ -3722,12 +3722,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.cs</span><pre><span></span><code><a id="__codelineno-3-1" name="__codelineno-3-1" href="#__codelineno-3-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-3-2" name="__codelineno-3-2" href="#__codelineno-3-2"></a><span class="k">void</span><span class="w"> </span><span class="nf">Merge</span><span class="p">(</span><span class="kt">int</span><span class="p">[]</span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-3-3" name="__codelineno-3-3" href="#__codelineno-3-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-3-3" name="__codelineno-3-3" href="#__codelineno-3-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-3-4" name="__codelineno-3-4" href="#__codelineno-3-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-3-5" name="__codelineno-3-5" href="#__codelineno-3-5"></a><span class="w"> </span><span class="kt">int</span><span class="p">[]</span><span class="w"> </span><span class="n">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">new</span><span class="w"> </span><span class="kt">int</span><span class="p">[</span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="m">1</span><span class="p">];</span>
|
||||
<a id="__codelineno-3-6" name="__codelineno-3-6" href="#__codelineno-3-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-3-7" name="__codelineno-3-7" href="#__codelineno-3-7"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="m">1</span><span class="p">,</span><span class="w"> </span><span class="n">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="m">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-3-8" name="__codelineno-3-8" href="#__codelineno-3-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-3-8" name="__codelineno-3-8" href="#__codelineno-3-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-3-9" name="__codelineno-3-9" href="#__codelineno-3-9"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-3-10" name="__codelineno-3-10" href="#__codelineno-3-10"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">])</span>
|
||||
<a id="__codelineno-3-11" name="__codelineno-3-11" href="#__codelineno-3-11"></a><span class="w"> </span><span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -3763,12 +3763,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.go</span><pre><span></span><code><a id="__codelineno-4-1" name="__codelineno-4-1" href="#__codelineno-4-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-4-2" name="__codelineno-4-2" href="#__codelineno-4-2"></a><span class="kd">func</span><span class="w"> </span><span class="nx">merge</span><span class="p">(</span><span class="nx">nums</span><span class="w"> </span><span class="p">[]</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="w"> </span><span class="kt">int</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-4-3" name="__codelineno-4-3" href="#__codelineno-4-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-4-3" name="__codelineno-4-3" href="#__codelineno-4-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-4-4" name="__codelineno-4-4" href="#__codelineno-4-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-4-5" name="__codelineno-4-5" href="#__codelineno-4-5"></a><span class="w"> </span><span class="nx">tmp</span><span class="w"> </span><span class="o">:=</span><span class="w"> </span><span class="nb">make</span><span class="p">([]</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="o">-</span><span class="nx">left</span><span class="o">+</span><span class="mi">1</span><span class="p">)</span>
|
||||
<a id="__codelineno-4-6" name="__codelineno-4-6" href="#__codelineno-4-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-4-7" name="__codelineno-4-7" href="#__codelineno-4-7"></a><span class="w"> </span><span class="nx">i</span><span class="p">,</span><span class="w"> </span><span class="nx">j</span><span class="p">,</span><span class="w"> </span><span class="nx">k</span><span class="w"> </span><span class="o">:=</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="o">+</span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="mi">0</span>
|
||||
<a id="__codelineno-4-8" name="__codelineno-4-8" href="#__codelineno-4-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-4-8" name="__codelineno-4-8" href="#__codelineno-4-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-4-9" name="__codelineno-4-9" href="#__codelineno-4-9"></a><span class="w"> </span><span class="k">for</span><span class="w"> </span><span class="nx">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="nx">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">right</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-4-10" name="__codelineno-4-10" href="#__codelineno-4-10"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">j</span><span class="p">]</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-4-11" name="__codelineno-4-11" href="#__codelineno-4-11"></a><span class="w"> </span><span class="nx">tmp</span><span class="p">[</span><span class="nx">k</span><span class="p">]</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span>
|
||||
@@ -3814,12 +3814,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.swift</span><pre><span></span><code><a id="__codelineno-5-1" name="__codelineno-5-1" href="#__codelineno-5-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-5-2" name="__codelineno-5-2" href="#__codelineno-5-2"></a><span class="kd">func</span> <span class="nf">merge</span><span class="p">(</span><span class="n">nums</span><span class="p">:</span> <span class="kr">inout</span> <span class="p">[</span><span class="nb">Int</span><span class="p">],</span> <span class="kr">left</span><span class="p">:</span> <span class="nb">Int</span><span class="p">,</span> <span class="n">mid</span><span class="p">:</span> <span class="nb">Int</span><span class="p">,</span> <span class="kr">right</span><span class="p">:</span> <span class="nb">Int</span><span class="p">)</span> <span class="p">{</span>
|
||||
<a id="__codelineno-5-3" name="__codelineno-5-3" href="#__codelineno-5-3"></a> <span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-5-3" name="__codelineno-5-3" href="#__codelineno-5-3"></a> <span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-5-4" name="__codelineno-5-4" href="#__codelineno-5-4"></a> <span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-5-5" name="__codelineno-5-5" href="#__codelineno-5-5"></a> <span class="kd">var</span> <span class="nv">tmp</span> <span class="p">=</span> <span class="nb">Array</span><span class="p">(</span><span class="n">repeating</span><span class="p">:</span> <span class="mi">0</span><span class="p">,</span> <span class="bp">count</span><span class="p">:</span> <span class="kr">right</span> <span class="o">-</span> <span class="kr">left</span> <span class="o">+</span> <span class="mi">1</span><span class="p">)</span>
|
||||
<a id="__codelineno-5-6" name="__codelineno-5-6" href="#__codelineno-5-6"></a> <span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-5-7" name="__codelineno-5-7" href="#__codelineno-5-7"></a> <span class="kd">var</span> <span class="nv">i</span> <span class="p">=</span> <span class="kr">left</span><span class="p">,</span> <span class="n">j</span> <span class="p">=</span> <span class="n">mid</span> <span class="o">+</span> <span class="mi">1</span><span class="p">,</span> <span class="n">k</span> <span class="p">=</span> <span class="mi">0</span>
|
||||
<a id="__codelineno-5-8" name="__codelineno-5-8" href="#__codelineno-5-8"></a> <span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-5-8" name="__codelineno-5-8" href="#__codelineno-5-8"></a> <span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-5-9" name="__codelineno-5-9" href="#__codelineno-5-9"></a> <span class="k">while</span> <span class="n">i</span> <span class="o"><=</span> <span class="n">mid</span><span class="p">,</span> <span class="n">j</span> <span class="o"><=</span> <span class="kr">right</span> <span class="p">{</span>
|
||||
<a id="__codelineno-5-10" name="__codelineno-5-10" href="#__codelineno-5-10"></a> <span class="k">if</span> <span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span> <span class="o"><=</span> <span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">]</span> <span class="p">{</span>
|
||||
<a id="__codelineno-5-11" name="__codelineno-5-11" href="#__codelineno-5-11"></a> <span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="p">=</span> <span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span>
|
||||
@@ -3866,14 +3866,14 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.js</span><pre><span></span><code><a id="__codelineno-6-1" name="__codelineno-6-1" href="#__codelineno-6-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-6-2" name="__codelineno-6-2" href="#__codelineno-6-2"></a><span class="kd">function</span><span class="w"> </span><span class="nx">merge</span><span class="p">(</span><span class="nx">nums</span><span class="p">,</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-6-3" name="__codelineno-6-3" href="#__codelineno-6-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-6-3" name="__codelineno-6-3" href="#__codelineno-6-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-6-4" name="__codelineno-6-4" href="#__codelineno-6-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-6-5" name="__codelineno-6-5" href="#__codelineno-6-5"></a><span class="w"> </span><span class="kd">const</span><span class="w"> </span><span class="nx">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="ow">new</span><span class="w"> </span><span class="nb">Array</span><span class="p">(</span><span class="nx">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="nx">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">);</span>
|
||||
<a id="__codelineno-6-6" name="__codelineno-6-6" href="#__codelineno-6-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-6-7" name="__codelineno-6-7" href="#__codelineno-6-7"></a><span class="w"> </span><span class="kd">let</span><span class="w"> </span><span class="nx">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span>
|
||||
<a id="__codelineno-6-8" name="__codelineno-6-8" href="#__codelineno-6-8"></a><span class="w"> </span><span class="nx">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">,</span>
|
||||
<a id="__codelineno-6-9" name="__codelineno-6-9" href="#__codelineno-6-9"></a><span class="w"> </span><span class="nx">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mf">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-6-10" name="__codelineno-6-10" href="#__codelineno-6-10"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-6-10" name="__codelineno-6-10" href="#__codelineno-6-10"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-6-11" name="__codelineno-6-11" href="#__codelineno-6-11"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="nx">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="nx">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-6-12" name="__codelineno-6-12" href="#__codelineno-6-12"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">j</span><span class="p">])</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-6-13" name="__codelineno-6-13" href="#__codelineno-6-13"></a><span class="w"> </span><span class="nx">tmp</span><span class="p">[</span><span class="nx">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -3910,14 +3910,14 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.ts</span><pre><span></span><code><a id="__codelineno-7-1" name="__codelineno-7-1" href="#__codelineno-7-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-7-2" name="__codelineno-7-2" href="#__codelineno-7-2"></a><span class="kd">function</span><span class="w"> </span><span class="nx">merge</span><span class="p">(</span><span class="nx">nums</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">[],</span><span class="w"> </span><span class="nx">left</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">)</span><span class="o">:</span><span class="w"> </span><span class="ow">void</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-7-3" name="__codelineno-7-3" href="#__codelineno-7-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-7-3" name="__codelineno-7-3" href="#__codelineno-7-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-7-4" name="__codelineno-7-4" href="#__codelineno-7-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-7-5" name="__codelineno-7-5" href="#__codelineno-7-5"></a><span class="w"> </span><span class="kd">const</span><span class="w"> </span><span class="nx">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="ow">new</span><span class="w"> </span><span class="nb">Array</span><span class="p">(</span><span class="nx">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="nx">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">);</span>
|
||||
<a id="__codelineno-7-6" name="__codelineno-7-6" href="#__codelineno-7-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-7-7" name="__codelineno-7-7" href="#__codelineno-7-7"></a><span class="w"> </span><span class="kd">let</span><span class="w"> </span><span class="nx">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span>
|
||||
<a id="__codelineno-7-8" name="__codelineno-7-8" href="#__codelineno-7-8"></a><span class="w"> </span><span class="nx">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">,</span>
|
||||
<a id="__codelineno-7-9" name="__codelineno-7-9" href="#__codelineno-7-9"></a><span class="w"> </span><span class="nx">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mf">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-7-10" name="__codelineno-7-10" href="#__codelineno-7-10"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-7-10" name="__codelineno-7-10" href="#__codelineno-7-10"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-7-11" name="__codelineno-7-11" href="#__codelineno-7-11"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="nx">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="nx">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-7-12" name="__codelineno-7-12" href="#__codelineno-7-12"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">j</span><span class="p">])</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-7-13" name="__codelineno-7-13" href="#__codelineno-7-13"></a><span class="w"> </span><span class="nx">tmp</span><span class="p">[</span><span class="nx">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nx">nums</span><span class="p">[</span><span class="nx">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -3954,12 +3954,12 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.dart</span><pre><span></span><code><a id="__codelineno-8-1" name="__codelineno-8-1" href="#__codelineno-8-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-8-2" name="__codelineno-8-2" href="#__codelineno-8-2"></a><span class="kt">void</span><span class="w"> </span><span class="n">merge</span><span class="p">(</span><span class="n">List</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-8-3" name="__codelineno-8-3" href="#__codelineno-8-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-8-3" name="__codelineno-8-3" href="#__codelineno-8-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-8-4" name="__codelineno-8-4" href="#__codelineno-8-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-8-5" name="__codelineno-8-5" href="#__codelineno-8-5"></a><span class="w"> </span><span class="n">List</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">List</span><span class="p">.</span><span class="n">filled</span><span class="p">(</span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="m">1</span><span class="p">,</span><span class="w"> </span><span class="m">0</span><span class="p">);</span>
|
||||
<a id="__codelineno-8-6" name="__codelineno-8-6" href="#__codelineno-8-6"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-8-7" name="__codelineno-8-7" href="#__codelineno-8-7"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="m">1</span><span class="p">,</span><span class="w"> </span><span class="n">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="m">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-8-8" name="__codelineno-8-8" href="#__codelineno-8-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-8-8" name="__codelineno-8-8" href="#__codelineno-8-8"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-8-9" name="__codelineno-8-9" href="#__codelineno-8-9"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-8-10" name="__codelineno-8-10" href="#__codelineno-8-10"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">])</span>
|
||||
<a id="__codelineno-8-11" name="__codelineno-8-11" href="#__codelineno-8-11"></a><span class="w"> </span><span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -3995,13 +3995,13 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.rs</span><pre><span></span><code><a id="__codelineno-9-1" name="__codelineno-9-1" href="#__codelineno-9-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-9-2" name="__codelineno-9-2" href="#__codelineno-9-2"></a><span class="k">fn</span> <span class="nf">merge</span><span class="p">(</span><span class="n">nums</span>: <span class="kp">&</span><span class="nc">mut</span><span class="w"> </span><span class="p">[</span><span class="kt">i32</span><span class="p">],</span><span class="w"> </span><span class="n">left</span>: <span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">mid</span>: <span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">right</span>: <span class="kt">usize</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-9-3" name="__codelineno-9-3" href="#__codelineno-9-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-9-3" name="__codelineno-9-3" href="#__codelineno-9-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-9-4" name="__codelineno-9-4" href="#__codelineno-9-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-9-5" name="__codelineno-9-5" href="#__codelineno-9-5"></a><span class="w"> </span><span class="kd">let</span><span class="w"> </span><span class="n">tmp_size</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span>
|
||||
<a id="__codelineno-9-6" name="__codelineno-9-6" href="#__codelineno-9-6"></a><span class="w"> </span><span class="kd">let</span><span class="w"> </span><span class="k">mut</span><span class="w"> </span><span class="n">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="fm">vec!</span><span class="p">[</span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="n">tmp_size</span><span class="p">];</span>
|
||||
<a id="__codelineno-9-7" name="__codelineno-9-7" href="#__codelineno-9-7"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-9-8" name="__codelineno-9-8" href="#__codelineno-9-8"></a><span class="w"> </span><span class="kd">let</span><span class="w"> </span><span class="p">(</span><span class="k">mut</span><span class="w"> </span><span class="n">i</span><span class="p">,</span><span class="w"> </span><span class="k">mut</span><span class="w"> </span><span class="n">j</span><span class="p">,</span><span class="w"> </span><span class="k">mut</span><span class="w"> </span><span class="n">k</span><span class="p">)</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="mi">0</span><span class="p">);</span>
|
||||
<a id="__codelineno-9-9" name="__codelineno-9-9" href="#__codelineno-9-9"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-9-9" name="__codelineno-9-9" href="#__codelineno-9-9"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-9-10" name="__codelineno-9-10" href="#__codelineno-9-10"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-9-11" name="__codelineno-9-11" href="#__codelineno-9-11"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">]</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-9-12" name="__codelineno-9-12" href="#__codelineno-9-12"></a><span class="w"> </span><span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">];</span>
|
||||
@@ -4045,13 +4045,13 @@
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">merge_sort.c</span><pre><span></span><code><a id="__codelineno-10-1" name="__codelineno-10-1" href="#__codelineno-10-1"></a><span class="cm">/* 合并左子数组和右子数组 */</span>
|
||||
<a id="__codelineno-10-2" name="__codelineno-10-2" href="#__codelineno-10-2"></a><span class="kt">void</span><span class="w"> </span><span class="nf">merge</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="o">*</span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-10-3" name="__codelineno-10-3" href="#__codelineno-10-3"></a><span class="w"> </span><span class="c1">// 左子数组区间 [left, mid], 右子数组区间 [mid+1, right]</span>
|
||||
<a id="__codelineno-10-3" name="__codelineno-10-3" href="#__codelineno-10-3"></a><span class="w"> </span><span class="c1">// 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]</span>
|
||||
<a id="__codelineno-10-4" name="__codelineno-10-4" href="#__codelineno-10-4"></a><span class="w"> </span><span class="c1">// 创建一个临时数组 tmp ，用于存放合并后的结果</span>
|
||||
<a id="__codelineno-10-5" name="__codelineno-10-5" href="#__codelineno-10-5"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">tmpSize</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">right</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="n">left</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span>
|
||||
<a id="__codelineno-10-6" name="__codelineno-10-6" href="#__codelineno-10-6"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="o">*</span><span class="n">tmp</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="o">*</span><span class="p">)</span><span class="n">malloc</span><span class="p">(</span><span class="n">tmpSize</span><span class="w"> </span><span class="o">*</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="kt">int</span><span class="p">));</span>
|
||||
<a id="__codelineno-10-7" name="__codelineno-10-7" href="#__codelineno-10-7"></a><span class="w"> </span><span class="c1">// 初始化左子数组和右子数组的起始索引</span>
|
||||
<a id="__codelineno-10-8" name="__codelineno-10-8" href="#__codelineno-10-8"></a><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mi">1</span><span class="p">,</span><span class="w"> </span><span class="n">k</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
||||
<a id="__codelineno-10-9" name="__codelineno-10-9" href="#__codelineno-10-9"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-10-9" name="__codelineno-10-9" href="#__codelineno-10-9"></a><span class="w"> </span><span class="c1">// 当左右子数组都还有元素时，进行比较并将较小的元素复制到临时数组中</span>
|
||||
<a id="__codelineno-10-10" name="__codelineno-10-10" href="#__codelineno-10-10"></a><span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="n">i</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">mid</span><span class="w"> </span><span class="o">&&</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-10-11" name="__codelineno-10-11" href="#__codelineno-10-11"></a><span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="p">]</span><span class="w"> </span><span class="o"><=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">j</span><span class="p">])</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-10-12" name="__codelineno-10-12" href="#__codelineno-10-12"></a><span class="w"> </span><span class="n">tmp</span><span class="p">[</span><span class="n">k</span><span class="o">++</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nums</span><span class="p">[</span><span class="n">i</span><span class="o">++</span><span class="p">];</span>
|
||||
@@ -4144,8 +4144,8 @@
|
||||
</div>
|
||||
<h2 id="1162">11.6.2 算法特性<a class="headerlink" href="#1162" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n \log n)\)</span>、非自适应排序</strong>：划分产生高度为 <span class="arithmatex">\(\log n\)</span> 的递归树，每层合并的总操作数量为 <span class="arithmatex">\(n\)</span> ，因此总体时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(n)\)</span>、非原地排序</strong>：递归深度为 <span class="arithmatex">\(\log n\)</span> ，使用 <span class="arithmatex">\(O(\log n)\)</span> 大小的栈帧空间。合并操作需要借助辅助数组实现，使用 <span class="arithmatex">\(O(n)\)</span> 大小的额外空间。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span>、非自适应排序</strong>：划分产生高度为 <span class="arithmatex">\(\log n\)</span> 的递归树，每层合并的总操作数量为 <span class="arithmatex">\(n\)</span> ，因此总体时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(n)\)</span>、非原地排序</strong>：递归深度为 <span class="arithmatex">\(\log n\)</span> ，使用 <span class="arithmatex">\(O(\log n)\)</span> 大小的栈帧空间。合并操作需要借助辅助数组实现，使用 <span class="arithmatex">\(O(n)\)</span> 大小的额外空间。</li>
|
||||
<li><strong>稳定排序</strong>：在合并过程中，相等元素的次序保持不变。</li>
|
||||
</ul>
|
||||
<h2 id="1163">11.6.3 链表排序<a class="headerlink" href="#1163" title="Permanent link">¶</a></h2>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -4113,8 +4113,8 @@
|
||||
</div>
|
||||
<h2 id="1152">11.5.2 算法特性<a class="headerlink" href="#1152" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(n \log n)\)</span>、自适应排序</strong>：在平均情况下，哨兵划分的递归层数为 <span class="arithmatex">\(\log n\)</span> ，每层中的总循环数为 <span class="arithmatex">\(n\)</span> ，总体使用 <span class="arithmatex">\(O(n \log n)\)</span> 时间。在最差情况下，每轮哨兵划分操作都将长度为 <span class="arithmatex">\(n\)</span> 的数组划分为长度为 <span class="arithmatex">\(0\)</span> 和 <span class="arithmatex">\(n - 1\)</span> 的两个子数组，此时递归层数达到 <span class="arithmatex">\(n\)</span> ，每层中的循环数为 <span class="arithmatex">\(n\)</span> ，总体使用 <span class="arithmatex">\(O(n^2)\)</span> 时间。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(n)\)</span>、原地排序</strong>：在输入数组完全倒序的情况下，达到最差递归深度 <span class="arithmatex">\(n\)</span> ，使用 <span class="arithmatex">\(O(n)\)</span> 栈帧空间。排序操作是在原数组上进行的，未借助额外数组。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n \log n)\)</span>、自适应排序</strong>：在平均情况下，哨兵划分的递归层数为 <span class="arithmatex">\(\log n\)</span> ，每层中的总循环数为 <span class="arithmatex">\(n\)</span> ，总体使用 <span class="arithmatex">\(O(n \log n)\)</span> 时间。在最差情况下，每轮哨兵划分操作都将长度为 <span class="arithmatex">\(n\)</span> 的数组划分为长度为 <span class="arithmatex">\(0\)</span> 和 <span class="arithmatex">\(n - 1\)</span> 的两个子数组，此时递归层数达到 <span class="arithmatex">\(n\)</span> ，每层中的循环数为 <span class="arithmatex">\(n\)</span> ，总体使用 <span class="arithmatex">\(O(n^2)\)</span> 时间。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(n)\)</span>、原地排序</strong>：在输入数组完全倒序的情况下，达到最差递归深度 <span class="arithmatex">\(n\)</span> ，使用 <span class="arithmatex">\(O(n)\)</span> 栈帧空间。排序操作是在原数组上进行的，未借助额外数组。</li>
|
||||
<li><strong>非稳定排序</strong>：在哨兵划分的最后一步，基准数可能会被交换至相等元素的右侧。</li>
|
||||
</ul>
|
||||
<h2 id="1153">11.5.3 快速排序为什么快<a class="headerlink" href="#1153" title="Permanent link">¶</a></h2>
|
||||
@@ -4134,7 +4134,7 @@
|
||||
<div class="tabbed-content">
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.py</span><pre><span></span><code><a id="__codelineno-24-1" name="__codelineno-24-1" href="#__codelineno-24-1"></a><span class="k">def</span> <span class="nf">median_three</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">nums</span><span class="p">:</span> <span class="nb">list</span><span class="p">[</span><span class="nb">int</span><span class="p">],</span> <span class="n">left</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">mid</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">right</span><span class="p">:</span> <span class="nb">int</span><span class="p">)</span> <span class="o">-></span> <span class="nb">int</span><span class="p">:</span>
|
||||
<a id="__codelineno-24-2" name="__codelineno-24-2" href="#__codelineno-24-2"></a><span class="w"> </span><span class="sd">"""选取三个元素的中位数"""</span>
|
||||
<a id="__codelineno-24-2" name="__codelineno-24-2" href="#__codelineno-24-2"></a><span class="w"> </span><span class="sd">"""选取三个候选元素的中位数"""</span>
|
||||
<a id="__codelineno-24-3" name="__codelineno-24-3" href="#__codelineno-24-3"></a> <span class="c1"># 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-24-4" name="__codelineno-24-4" href="#__codelineno-24-4"></a> <span class="c1"># 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
<a id="__codelineno-24-5" name="__codelineno-24-5" href="#__codelineno-24-5"></a> <span class="k">if</span> <span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">left</span><span class="p">]</span> <span class="o"><</span> <span class="n">nums</span><span class="p">[</span><span class="n">mid</span><span class="p">])</span> <span class="o">^</span> <span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="n">left</span><span class="p">]</span> <span class="o"><</span> <span class="n">nums</span><span class="p">[</span><span class="n">right</span><span class="p">]):</span>
|
||||
@@ -4164,7 +4164,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.cpp</span><pre><span></span><code><a id="__codelineno-25-1" name="__codelineno-25-1" href="#__codelineno-25-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.cpp</span><pre><span></span><code><a id="__codelineno-25-1" name="__codelineno-25-1" href="#__codelineno-25-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-25-2" name="__codelineno-25-2" href="#__codelineno-25-2"></a><span class="kt">int</span><span class="w"> </span><span class="nf">medianThree</span><span class="p">(</span><span class="n">vector</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="o">&</span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-25-3" name="__codelineno-25-3" href="#__codelineno-25-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-25-4" name="__codelineno-25-4" href="#__codelineno-25-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4197,7 +4197,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.java</span><pre><span></span><code><a id="__codelineno-26-1" name="__codelineno-26-1" href="#__codelineno-26-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.java</span><pre><span></span><code><a id="__codelineno-26-1" name="__codelineno-26-1" href="#__codelineno-26-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-26-2" name="__codelineno-26-2" href="#__codelineno-26-2"></a><span class="kt">int</span><span class="w"> </span><span class="nf">medianThree</span><span class="p">(</span><span class="kt">int</span><span class="o">[]</span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-26-3" name="__codelineno-26-3" href="#__codelineno-26-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-26-4" name="__codelineno-26-4" href="#__codelineno-26-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4230,7 +4230,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.cs</span><pre><span></span><code><a id="__codelineno-27-1" name="__codelineno-27-1" href="#__codelineno-27-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.cs</span><pre><span></span><code><a id="__codelineno-27-1" name="__codelineno-27-1" href="#__codelineno-27-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-27-2" name="__codelineno-27-2" href="#__codelineno-27-2"></a><span class="kt">int</span><span class="w"> </span><span class="nf">MedianThree</span><span class="p">(</span><span class="kt">int</span><span class="p">[]</span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-27-3" name="__codelineno-27-3" href="#__codelineno-27-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-27-4" name="__codelineno-27-4" href="#__codelineno-27-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4263,7 +4263,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.go</span><pre><span></span><code><a id="__codelineno-28-1" name="__codelineno-28-1" href="#__codelineno-28-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.go</span><pre><span></span><code><a id="__codelineno-28-1" name="__codelineno-28-1" href="#__codelineno-28-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-28-2" name="__codelineno-28-2" href="#__codelineno-28-2"></a><span class="kd">func</span><span class="w"> </span><span class="p">(</span><span class="nx">q</span><span class="w"> </span><span class="o">*</span><span class="nx">quickSortMedian</span><span class="p">)</span><span class="w"> </span><span class="nx">medianThree</span><span class="p">(</span><span class="nx">nums</span><span class="w"> </span><span class="p">[]</span><span class="kt">int</span><span class="p">,</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="w"> </span><span class="kt">int</span><span class="p">)</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-28-3" name="__codelineno-28-3" href="#__codelineno-28-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码（!= 在这里起到异或的作用）</span>
|
||||
<a id="__codelineno-28-4" name="__codelineno-28-4" href="#__codelineno-28-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4300,7 +4300,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.swift</span><pre><span></span><code><a id="__codelineno-29-1" name="__codelineno-29-1" href="#__codelineno-29-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.swift</span><pre><span></span><code><a id="__codelineno-29-1" name="__codelineno-29-1" href="#__codelineno-29-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-29-2" name="__codelineno-29-2" href="#__codelineno-29-2"></a><span class="kd">func</span> <span class="nf">medianThree</span><span class="p">(</span><span class="n">nums</span><span class="p">:</span> <span class="p">[</span><span class="nb">Int</span><span class="p">],</span> <span class="kr">left</span><span class="p">:</span> <span class="nb">Int</span><span class="p">,</span> <span class="n">mid</span><span class="p">:</span> <span class="nb">Int</span><span class="p">,</span> <span class="kr">right</span><span class="p">:</span> <span class="nb">Int</span><span class="p">)</span> <span class="p">-></span> <span class="nb">Int</span> <span class="p">{</span>
|
||||
<a id="__codelineno-29-3" name="__codelineno-29-3" href="#__codelineno-29-3"></a> <span class="k">if</span> <span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="kr">left</span><span class="p">]</span> <span class="o"><</span> <span class="n">nums</span><span class="p">[</span><span class="n">mid</span><span class="p">])</span> <span class="o">!=</span> <span class="p">(</span><span class="n">nums</span><span class="p">[</span><span class="kr">left</span><span class="p">]</span> <span class="o"><</span> <span class="n">nums</span><span class="p">[</span><span class="kr">right</span><span class="p">])</span> <span class="p">{</span>
|
||||
<a id="__codelineno-29-4" name="__codelineno-29-4" href="#__codelineno-29-4"></a> <span class="k">return</span> <span class="kr">left</span>
|
||||
@@ -4322,7 +4322,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.js</span><pre><span></span><code><a id="__codelineno-30-1" name="__codelineno-30-1" href="#__codelineno-30-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.js</span><pre><span></span><code><a id="__codelineno-30-1" name="__codelineno-30-1" href="#__codelineno-30-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-30-2" name="__codelineno-30-2" href="#__codelineno-30-2"></a><span class="nx">medianThree</span><span class="p">(</span><span class="nx">nums</span><span class="p">,</span><span class="w"> </span><span class="nx">left</span><span class="p">,</span><span class="w"> </span><span class="nx">mid</span><span class="p">,</span><span class="w"> </span><span class="nx">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-30-3" name="__codelineno-30-3" href="#__codelineno-30-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-30-4" name="__codelineno-30-4" href="#__codelineno-30-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4357,7 +4357,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.ts</span><pre><span></span><code><a id="__codelineno-31-1" name="__codelineno-31-1" href="#__codelineno-31-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.ts</span><pre><span></span><code><a id="__codelineno-31-1" name="__codelineno-31-1" href="#__codelineno-31-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-31-2" name="__codelineno-31-2" href="#__codelineno-31-2"></a><span class="nx">medianThree</span><span class="p">(</span>
|
||||
<a id="__codelineno-31-3" name="__codelineno-31-3" href="#__codelineno-31-3"></a><span class="w"> </span><span class="nx">nums</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">[],</span>
|
||||
<a id="__codelineno-31-4" name="__codelineno-31-4" href="#__codelineno-31-4"></a><span class="w"> </span><span class="nx">left</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="p">,</span>
|
||||
@@ -4406,7 +4406,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.dart</span><pre><span></span><code><a id="__codelineno-32-1" name="__codelineno-32-1" href="#__codelineno-32-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.dart</span><pre><span></span><code><a id="__codelineno-32-1" name="__codelineno-32-1" href="#__codelineno-32-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-32-2" name="__codelineno-32-2" href="#__codelineno-32-2"></a><span class="kt">int</span><span class="w"> </span><span class="n">_medianThree</span><span class="p">(</span><span class="n">List</span><span class="o"><</span><span class="kt">int</span><span class="o">></span><span class="w"> </span><span class="n">nums</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-32-3" name="__codelineno-32-3" href="#__codelineno-32-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-32-4" name="__codelineno-32-4" href="#__codelineno-32-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4437,7 +4437,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.rs</span><pre><span></span><code><a id="__codelineno-33-1" name="__codelineno-33-1" href="#__codelineno-33-1"></a><span class="cm">/* 选取三个元素的中位数 */</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.rs</span><pre><span></span><code><a id="__codelineno-33-1" name="__codelineno-33-1" href="#__codelineno-33-1"></a><span class="cm">/* 选取三个候选元素的中位数 */</span>
|
||||
<a id="__codelineno-33-2" name="__codelineno-33-2" href="#__codelineno-33-2"></a><span class="k">fn</span> <span class="nf">median_three</span><span class="p">(</span><span class="n">nums</span>: <span class="kp">&</span><span class="nc">mut</span><span class="w"> </span><span class="p">[</span><span class="kt">i32</span><span class="p">],</span><span class="w"> </span><span class="n">left</span>: <span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">mid</span>: <span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">right</span>: <span class="kt">usize</span><span class="p">)</span><span class="w"> </span>-> <span class="kt">usize</span> <span class="p">{</span>
|
||||
<a id="__codelineno-33-3" name="__codelineno-33-3" href="#__codelineno-33-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-33-4" name="__codelineno-33-4" href="#__codelineno-33-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4473,7 +4473,7 @@
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.c</span><pre><span></span><code><a id="__codelineno-34-1" name="__codelineno-34-1" href="#__codelineno-34-1"></a><span class="cm">/* 快速排序类（中位基准数优化） */</span>
|
||||
<a id="__codelineno-34-2" name="__codelineno-34-2" href="#__codelineno-34-2"></a><span class="c1">// 选取三个元素的中位数</span>
|
||||
<a id="__codelineno-34-2" name="__codelineno-34-2" href="#__codelineno-34-2"></a><span class="c1">// 选取三个候选元素的中位数</span>
|
||||
<a id="__codelineno-34-3" name="__codelineno-34-3" href="#__codelineno-34-3"></a><span class="kt">int</span><span class="w"> </span><span class="nf">medianThree</span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">nums</span><span class="p">[],</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">left</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">mid</span><span class="p">,</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">right</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-34-4" name="__codelineno-34-4" href="#__codelineno-34-4"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-34-5" name="__codelineno-34-5" href="#__codelineno-34-5"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
@@ -4506,7 +4506,7 @@
|
||||
</code></pre></div>
|
||||
</div>
|
||||
<div class="tabbed-block">
|
||||
<div class="highlight"><span class="filename">quick_sort.zig</span><pre><span></span><code><a id="__codelineno-35-1" name="__codelineno-35-1" href="#__codelineno-35-1"></a><span class="c1">// 选取三个元素的中位数</span>
|
||||
<div class="highlight"><span class="filename">quick_sort.zig</span><pre><span></span><code><a id="__codelineno-35-1" name="__codelineno-35-1" href="#__codelineno-35-1"></a><span class="c1">// 选取三个候选元素的中位数</span>
|
||||
<a id="__codelineno-35-2" name="__codelineno-35-2" href="#__codelineno-35-2"></a><span class="k">fn</span><span class="w"> </span><span class="n">medianThree</span><span class="p">(</span><span class="n">nums</span><span class="o">:</span><span class="w"> </span><span class="p">[]</span><span class="kt">i32</span><span class="p">,</span><span class="w"> </span><span class="n">left</span><span class="o">:</span><span class="w"> </span><span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">mid</span><span class="o">:</span><span class="w"> </span><span class="kt">usize</span><span class="p">,</span><span class="w"> </span><span class="n">right</span><span class="o">:</span><span class="w"> </span><span class="kt">usize</span><span class="p">)</span><span class="w"> </span><span class="kt">usize</span><span class="w"> </span><span class="p">{</span>
|
||||
<a id="__codelineno-35-3" name="__codelineno-35-3" href="#__codelineno-35-3"></a><span class="w"> </span><span class="c1">// 此处使用异或运算来简化代码</span>
|
||||
<a id="__codelineno-35-4" name="__codelineno-35-4" href="#__codelineno-35-4"></a><span class="w"> </span><span class="c1">// 异或规则为 0 ^ 0 = 1 ^ 1 = 0, 0 ^ 1 = 1 ^ 0 = 1</span>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3531,7 +3531,7 @@
|
||||
<div class="arithmatex">\[
|
||||
x_k = \lfloor\frac{x}{d^{k-1}}\rfloor \bmod d
|
||||
\]</div>
|
||||
<p>其中 <span class="arithmatex">\(\lfloor a \rfloor\)</span> 表示对浮点数 <span class="arithmatex">\(a\)</span> 向下取整，而 <span class="arithmatex">\(\bmod \: d\)</span> 表示对 <span class="arithmatex">\(d\)</span> 取余。对于学号数据，<span class="arithmatex">\(d = 10\)</span> 且 <span class="arithmatex">\(k \in [1, 8]\)</span> 。</p>
|
||||
<p>其中 <span class="arithmatex">\(\lfloor a \rfloor\)</span> 表示对浮点数 <span class="arithmatex">\(a\)</span> 向下取整，而 <span class="arithmatex">\(\bmod \: d\)</span> 表示对 <span class="arithmatex">\(d\)</span> 取模（取余）。对于学号数据，<span class="arithmatex">\(d = 10\)</span> 且 <span class="arithmatex">\(k \in [1, 8]\)</span> 。</p>
|
||||
<p>此外，我们需要小幅改动计数排序代码，使之可以根据数字的第 <span class="arithmatex">\(k\)</span> 位进行排序：</p>
|
||||
<div class="tabbed-set tabbed-alternate" data-tabs="1:12"><input checked="checked" id="__tabbed_1_1" name="__tabbed_1" type="radio" /><input id="__tabbed_1_2" name="__tabbed_1" type="radio" /><input id="__tabbed_1_3" name="__tabbed_1" type="radio" /><input id="__tabbed_1_4" name="__tabbed_1" type="radio" /><input id="__tabbed_1_5" name="__tabbed_1" type="radio" /><input id="__tabbed_1_6" name="__tabbed_1" type="radio" /><input id="__tabbed_1_7" name="__tabbed_1" type="radio" /><input id="__tabbed_1_8" name="__tabbed_1" type="radio" /><input id="__tabbed_1_9" name="__tabbed_1" type="radio" /><input id="__tabbed_1_10" name="__tabbed_1" type="radio" /><input id="__tabbed_1_11" name="__tabbed_1" type="radio" /><input id="__tabbed_1_12" name="__tabbed_1" type="radio" /><div class="tabbed-labels"><label for="__tabbed_1_1">Python</label><label for="__tabbed_1_2">C++</label><label for="__tabbed_1_3">Java</label><label for="__tabbed_1_4">C#</label><label for="__tabbed_1_5">Go</label><label for="__tabbed_1_6">Swift</label><label for="__tabbed_1_7">JS</label><label for="__tabbed_1_8">TS</label><label for="__tabbed_1_9">Dart</label><label for="__tabbed_1_10">Rust</label><label for="__tabbed_1_11">C</label><label for="__tabbed_1_12">Zig</label></div>
|
||||
<div class="tabbed-content">
|
||||
@@ -4174,8 +4174,8 @@ x_k = \lfloor\frac{x}{d^{k-1}}\rfloor \bmod d
|
||||
<h2 id="11102">11.10.2 算法特性<a class="headerlink" href="#11102" title="Permanent link">¶</a></h2>
|
||||
<p>相较于计数排序，基数排序适用于数值范围较大的情况，<strong>但前提是数据必须可以表示为固定位数的格式，且位数不能过大</strong>。例如，浮点数不适合使用基数排序，因为其位数 <span class="arithmatex">\(k\)</span> 过大，可能导致时间复杂度 <span class="arithmatex">\(O(nk) \gg O(n^2)\)</span> 。</p>
|
||||
<ul>
|
||||
<li><strong>时间复杂度 <span class="arithmatex">\(O(nk)\)</span></strong>：设数据量为 <span class="arithmatex">\(n\)</span>、数据为 <span class="arithmatex">\(d\)</span> 进制、最大位数为 <span class="arithmatex">\(k\)</span> ，则对某一位执行计数排序使用 <span class="arithmatex">\(O(n + d)\)</span> 时间，排序所有 <span class="arithmatex">\(k\)</span> 位使用 <span class="arithmatex">\(O((n + d)k)\)</span> 时间。通常情况下，<span class="arithmatex">\(d\)</span> 和 <span class="arithmatex">\(k\)</span> 都相对较小，时间复杂度趋向 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(n + d)\)</span>、非原地排序</strong>：与计数排序相同，基数排序需要借助长度为 <span class="arithmatex">\(n\)</span> 和 <span class="arithmatex">\(d\)</span> 的数组 <code>res</code> 和 <code>counter</code> 。</li>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(nk)\)</span></strong>：设数据量为 <span class="arithmatex">\(n\)</span>、数据为 <span class="arithmatex">\(d\)</span> 进制、最大位数为 <span class="arithmatex">\(k\)</span> ，则对某一位执行计数排序使用 <span class="arithmatex">\(O(n + d)\)</span> 时间，排序所有 <span class="arithmatex">\(k\)</span> 位使用 <span class="arithmatex">\(O((n + d)k)\)</span> 时间。通常情况下，<span class="arithmatex">\(d\)</span> 和 <span class="arithmatex">\(k\)</span> 都相对较小，时间复杂度趋向 <span class="arithmatex">\(O(n)\)</span> 。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(n + d)\)</span>、非原地排序</strong>：与计数排序相同，基数排序需要借助长度为 <span class="arithmatex">\(n\)</span> 和 <span class="arithmatex">\(d\)</span> 的数组 <code>res</code> 和 <code>counter</code> 。</li>
|
||||
<li><strong>稳定排序</strong>：当计数排序稳定时，基数排序也稳定；当计数排序不稳定时，基数排序无法保证得到正确的排序结果。</li>
|
||||
</ul>
|
||||
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3762,7 +3762,7 @@
|
||||
<h2 id="1121">11.2.1 算法特性<a class="headerlink" href="#1121" title="Permanent link">¶</a></h2>
|
||||
<ul>
|
||||
<li><strong>时间复杂度为 <span class="arithmatex">\(O(n^2)\)</span>、非自适应排序</strong>：外循环共 <span class="arithmatex">\(n - 1\)</span> 轮，第一轮的未排序区间长度为 <span class="arithmatex">\(n\)</span> ，最后一轮的未排序区间长度为 <span class="arithmatex">\(2\)</span> ，即各轮外循环分别包含 <span class="arithmatex">\(n\)</span>、<span class="arithmatex">\(n - 1\)</span>、<span class="arithmatex">\(\dots\)</span>、<span class="arithmatex">\(3\)</span>、<span class="arithmatex">\(2\)</span> 轮内循环，求和为 <span class="arithmatex">\(\frac{(n - 1)(n + 2)}{2}\)</span> 。</li>
|
||||
<li><strong>空间复杂度 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：指针 <span class="arithmatex">\(i\)</span> 和 <span class="arithmatex">\(j\)</span> 使用常数大小的额外空间。</li>
|
||||
<li><strong>空间复杂度为 <span class="arithmatex">\(O(1)\)</span>、原地排序</strong>：指针 <span class="arithmatex">\(i\)</span> 和 <span class="arithmatex">\(j\)</span> 使用常数大小的额外空间。</li>
|
||||
<li><strong>非稳定排序</strong>：如图 11-3 所示，元素 <code>nums[i]</code> 有可能被交换至与其相等的元素的右边，导致两者的相对顺序发生改变。</li>
|
||||
</ul>
|
||||
<p><a class="glightbox" href="../selection_sort.assets/selection_sort_instability.png" data-type="image" data-width="100%" data-height="auto" data-desc-position="bottom"><img alt="选择排序非稳定示例" class="animation-figure" src="../selection_sort.assets/selection_sort_instability.png" /></a></p>
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
|
||||
@@ -1719,7 +1719,7 @@
|
||||
|
||||
|
||||
<span class="md-ellipsis">
|
||||
8.3 Top-K 问题
|
||||
8.3 Top-k 问题
|
||||
</span>
|
||||
|
||||
|
||||
@@ -3533,8 +3533,7 @@
|
||||
<h3 id="2-q-a">2. Q & A<a class="headerlink" href="#2-q-a" title="Permanent link">¶</a></h3>
|
||||
<div class="admonition question">
|
||||
<p class="admonition-title">排序算法稳定性在什么情况下是必需的？</p>
|
||||
<p>在现实中，我们有可能是基于对象的某个属性进行排序。例如，学生有姓名和身高两个属性，我们希望实现一个多级排序：</p>
|
||||
<p>先按照姓名进行排序，得到 <code>(A, 180) (B, 185) (C, 170) (D, 170)</code> ；再对身高进行排序。由于排序算法不稳定，因此可能得到 <code>(D, 170) (C, 170) (A, 180) (B, 185)</code> 。</p>
|
||||
<p>在现实中，我们有可能基于对象的某个属性进行排序。例如，学生有姓名和身高两个属性，我们希望实现一个多级排序：先按照姓名进行排序，得到 <code>(A, 180) (B, 185) (C, 170) (D, 170)</code> ；再对身高进行排序。由于排序算法不稳定，因此可能得到 <code>(D, 170) (C, 170) (A, 180) (B, 185)</code> 。</p>
|
||||
<p>可以发现，学生 D 和 C 的位置发生了交换，姓名的有序性被破坏了，而这是我们不希望看到的。</p>
|
||||
</div>
|
||||
<div class="admonition question">
|
||||
|
||||
Reference in New Issue
Block a user