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fix(csharp): Modify method name to PascalCase, simplify new expression (#840)

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* Modify method name to PascalCase(array and linked list)

* Modify method name to PascalCase(backtracking)

* Modify method name to PascalCase(computational complexity)

* Modify method name to PascalCase(divide and conquer)

* Modify method name to PascalCase(dynamic programming)

* Modify method name to PascalCase(graph)

* Modify method name to PascalCase(greedy)

* Modify method name to PascalCase(hashing)

* Modify method name to PascalCase(heap)

* Modify method name to PascalCase(searching)

* Modify method name to PascalCase(sorting)

* Modify method name to PascalCase(stack and queue)

* Modify method name to PascalCase(tree)

* local check
This commit is contained in:
hpstory
2023-10-08 01:33:46 +08:00
committed by GitHub
parent 6f7e768cb7
commit f62256bee1
129 changed files with 1186 additions and 1192 deletions
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codes/csharp/chapter_tree/avl_tree.cs
+58 -58
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@@ -11,77 +11,77 @@ class AVLTree {
public TreeNode? root; // 根节点
/* 获取节点高度 */
public int height(TreeNode? node) {
public int Height(TreeNode? node) {
// 空节点高度为 -1 ，叶节点高度为 0
return node == null ? -1 : node.height;
}
/* 更新节点高度 */
private void updateHeight(TreeNode node) {
private void UpdateHeight(TreeNode node) {
// 节点高度等于最高子树高度 + 1
node.height = Math.Max(height(node.left), height(node.right)) + 1;
node.height = Math.Max(Height(node.left), Height(node.right)) + 1;
}
/* 获取平衡因子 */
public int balanceFactor(TreeNode? node) {
public int BalanceFactor(TreeNode? node) {
// 空节点平衡因子为 0
if (node == null) return 0;
// 节点平衡因子 = 左子树高度 - 右子树高度
return height(node.left) - height(node.right);
return Height(node.left) - Height(node.right);
}
/* 右旋操作 */
TreeNode? rightRotate(TreeNode? node) {
TreeNode? RightRotate(TreeNode? node) {
TreeNode? child = node.left;
TreeNode? grandChild = child?.right;
// 以 child 为原点，将 node 向右旋转
child.right = node;
node.left = grandChild;
// 更新节点高度
updateHeight(node);
updateHeight(child);
UpdateHeight(node);
UpdateHeight(child);
// 返回旋转后子树的根节点
return child;
}
/* 左旋操作 */
TreeNode? leftRotate(TreeNode? node) {
TreeNode? LeftRotate(TreeNode? node) {
TreeNode? child = node.right;
TreeNode? grandChild = child?.left;
// 以 child 为原点，将 node 向左旋转
child.left = node;
node.right = grandChild;
// 更新节点高度
updateHeight(node);
updateHeight(child);
UpdateHeight(node);
UpdateHeight(child);
// 返回旋转后子树的根节点
return child;
}
/* 执行旋转操作，使该子树重新恢复平衡 */
TreeNode? rotate(TreeNode? node) {
TreeNode? Rotate(TreeNode? node) {
// 获取节点 node 的平衡因子
int balanceFactorInt = balanceFactor(node);
int balanceFactorInt = BalanceFactor(node);
// 左偏树
if (balanceFactorInt > 1) {
if (balanceFactor(node.left) >= 0) {
if (BalanceFactor(node.left) >= 0) {
// 右旋
return rightRotate(node);
return RightRotate(node);
} else {
// 先左旋后右旋
node.left = leftRotate(node?.left);
return rightRotate(node);
node.left = LeftRotate(node?.left);
return RightRotate(node);
}
}
// 右偏树
if (balanceFactorInt < -1) {
if (balanceFactor(node.right) <= 0) {
if (BalanceFactor(node.right) <= 0) {
// 左旋
return leftRotate(node);
return LeftRotate(node);
} else {
// 先右旋后左旋
node.right = rightRotate(node?.right);
return leftRotate(node);
node.right = RightRotate(node?.right);
return LeftRotate(node);
}
}
// 平衡树，无须旋转，直接返回
@@ -89,43 +89,43 @@ class AVLTree {
}
/* 插入节点 */
public void insert(int val) {
root = insertHelper(root, val);
public void Insert(int val) {
root = InsertHelper(root, val);
}
/* 递归插入节点（辅助方法） */
private TreeNode? insertHelper(TreeNode? node, int val) {
private TreeNode? InsertHelper(TreeNode? node, int val) {
if (node == null) return new TreeNode(val);
/* 1. 查找插入位置，并插入节点 */
if (val < node.val)
node.left = insertHelper(node.left, val);
node.left = InsertHelper(node.left, val);
else if (val > node.val)
node.right = insertHelper(node.right, val);
node.right = InsertHelper(node.right, val);
else
return node; // 重复节点不插入，直接返回
updateHeight(node); // 更新节点高度
UpdateHeight(node); // 更新节点高度
/* 2. 执行旋转操作，使该子树重新恢复平衡 */
node = rotate(node);
node = Rotate(node);
// 返回子树的根节点
return node;
}
/* 删除节点 */
public void remove(int val) {
root = removeHelper(root, val);
public void Remove(int val) {
root = RemoveHelper(root, val);
}
/* 递归删除节点（辅助方法） */
private TreeNode? removeHelper(TreeNode? node, int val) {
private TreeNode? RemoveHelper(TreeNode? node, int val) {
if (node == null) return null;
/* 1. 查找节点，并删除之 */
if (val < node.val)
node.left = removeHelper(node.left, val);
node.left = RemoveHelper(node.left, val);
else if (val > node.val)
node.right = removeHelper(node.right, val);
node.right = RemoveHelper(node.right, val);
else {
if (node.left == null || node.right == null) {
TreeNode? child = node.left != null ? node.left : node.right;
TreeNode? child = node.left ?? node.right;
// 子节点数量 = 0 ，直接删除 node 并返回
if (child == null)
return null;
@@ -138,19 +138,19 @@ class AVLTree {
while (temp.left != null) {
temp = temp.left;
}
node.right = removeHelper(node.right, temp.val);
node.right = RemoveHelper(node.right, temp.val);
node.val = temp.val;
}
}
updateHeight(node); // 更新节点高度
UpdateHeight(node); // 更新节点高度
/* 2. 执行旋转操作，使该子树重新恢复平衡 */
node = rotate(node);
node = Rotate(node);
// 返回子树的根节点
return node;
}
/* 查找节点 */
public TreeNode? search(int val) {
public TreeNode? Search(int val) {
TreeNode? cur = root;
// 循环查找，越过叶节点后跳出
while (cur != null) {
@@ -170,14 +170,14 @@ class AVLTree {
}
public class avl_tree {
static void testInsert(AVLTree tree, int val) {
tree.insert(val);
static void TestInsert(AVLTree tree, int val) {
tree.Insert(val);
Console.WriteLine("\n插入节点 " + val + " 后，AVL 树为");
PrintUtil.PrintTree(tree.root);
}
static void testRemove(AVLTree tree, int val) {
tree.remove(val);
static void TestRemove(AVLTree tree, int val) {
tree.Remove(val);
Console.WriteLine("\n删除节点 " + val + " 后，AVL 树为");
PrintUtil.PrintTree(tree.root);
}
@@ -185,32 +185,32 @@ public class avl_tree {
[Test]
public void Test() {
/* 初始化空 AVL 树 */
AVLTree avlTree = new AVLTree();
AVLTree avlTree = new();
/* 插入节点 */
// 请关注插入节点后，AVL 树是如何保持平衡的
testInsert(avlTree, 1);
testInsert(avlTree, 2);
testInsert(avlTree, 3);
testInsert(avlTree, 4);
testInsert(avlTree, 5);
testInsert(avlTree, 8);
testInsert(avlTree, 7);
testInsert(avlTree, 9);
testInsert(avlTree, 10);
testInsert(avlTree, 6);
TestInsert(avlTree, 1);
TestInsert(avlTree, 2);
TestInsert(avlTree, 3);
TestInsert(avlTree, 4);
TestInsert(avlTree, 5);
TestInsert(avlTree, 8);
TestInsert(avlTree, 7);
TestInsert(avlTree, 9);
TestInsert(avlTree, 10);
TestInsert(avlTree, 6);
/* 插入重复节点 */
testInsert(avlTree, 7);
TestInsert(avlTree, 7);
/* 删除节点 */
// 请关注删除节点后，AVL 树是如何保持平衡的
testRemove(avlTree, 8); // 删除度为 0 的节点
testRemove(avlTree, 5); // 删除度为 1 的节点
testRemove(avlTree, 4); // 删除度为 2 的节点
TestRemove(avlTree, 8); // 删除度为 0 的节点
TestRemove(avlTree, 5); // 删除度为 1 的节点
TestRemove(avlTree, 4); // 删除度为 2 的节点
/* 查询节点 */
TreeNode? node = avlTree.search(7);
TreeNode? node = avlTree.Search(7);
Console.WriteLine("\n查找到的节点对象为 " + node + "，节点值 = " + node?.val);
}
}