build

docs/chapter_sorting/merge_sort.md

@@ -630,9 +630,53 @@ comments: true
 === "Ruby"
 
     ```ruby title="merge_sort.rb"
-    [class]{}-[func]{merge}
+    ### 合并左子数组和右子数组 ###
+    def merge(nums, left, mid, right)
+      # 左子数组区间为 [left, mid], 右子数组区间为 [mid+1, right]
+      # 创建一个临时数组 tmp，用于存放合并后的结果
+      tmp = Array.new(right - left + 1, 0)
+      # 初始化左子数组和右子数组的起始索引
+      i, j, k = left, mid + 1, 0
+      # 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
+      while i <= mid && j <= right
+        if nums[i] <= nums[j]
+          tmp[k] = nums[i]
+          i += 1
+        else
+          tmp[k] = nums[j]
+          j += 1
+        end
+        k += 1
+      end
+      # 将左子数组和右子数组的剩余元素复制到临时数组中
+      while i <= mid
+        tmp[k] = nums[i]
+        i += 1
+        k += 1
+      end
+      while j <= right
+        tmp[k] = nums[j]
+        j += 1
+        k += 1
+      end
+      # 将临时数组 tmp 中的元素复制回原数组 nums 的对应区间
+      (0...tmp.length).each do |k|
+        nums[left + k] = tmp[k]
+      end
+    end
 
-    [class]{}-[func]{merge_sort}
+    ### 归并排序 ###
+    def merge_sort(nums, left, right)
+      # 终止条件
+      # 当子数组长度为 1 时终止递归
+      return if left >= right
+      # 划分阶段
+      mid = (left + right) / 2 # 计算中点
+      merge_sort(nums, left, mid) # 递归左子数组
+      merge_sort(nums, mid + 1, right) # 递归右子数组
+      # 合并阶段
+      merge(nums, left, mid, right)
+    end
     ```
 
 === "Zig"