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Reformat the C# codes.

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Disable creating new line before open brace.
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krahets
2023-04-23 03:03:12 +08:00
parent ac6eece4f3
commit 73dcb4cea9
49 changed files with 561 additions and 1135 deletions
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84
codes/csharp/chapter_tree/avl_tree.cs
View File

@@ -10,27 +10,23 @@ using NUnit.Framework;
namespace hello_algo.chapter_tree;
/* AVL 树 */
class AVLTree
{
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;
}
/* 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
@@ -38,8 +34,7 @@ class AVLTree
}
/* 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
@@ -53,8 +48,7 @@ class AVLTree
}
/* 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
@@ -68,35 +62,26 @@ class AVLTree
}
/* 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);
// 左偏树
if (balanceFactorInt > 1)
{
if (balanceFactor(node.left) >= 0)
{
if (balanceFactorInt > 1) {
if (balanceFactor(node.left) >= 0) {
// 右旋
return rightRotate(node);
}
else
{
} else {
// 先左旋后右旋
node.left = leftRotate(node?.left);
return rightRotate(node);
}
}
// 右偏树
if (balanceFactorInt < -1)
{
if (balanceFactor(node.right) <= 0)
{
if (balanceFactorInt < -1) {
if (balanceFactor(node.right) <= 0) {
// 左旋
return leftRotate(node);
}
else
{
} else {
// 先右旋后左旋
node.right = rightRotate(node?.right);
return leftRotate(node);
@@ -107,14 +92,12 @@ class AVLTree
}
/* 插入节点 */
public void insert(int 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)
@@ -131,24 +114,20 @@ class AVLTree
}
/* 删除节点 */
public void remove(int 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);
else if (val > node.val)
node.right = removeHelper(node.right, val);
else
{
if (node.left == null || node.right == null)
{
else {
if (node.left == null || node.right == null) {
TreeNode? child = node.left != null ? node.left : node.right;
// 子节点数量 = 0 ，直接删除 node 并返回
if (child == null)
@@ -156,13 +135,10 @@ class AVLTree
// 子节点数量 = 1 ，直接删除 node
else
node = child;
}
else
{
} else {
// 子节点数量 = 2 ，则将中序遍历的下个节点删除，并用该节点替换当前节点
TreeNode? temp = node.right;
while (temp.left != null)
{
while (temp.left != null) {
temp = temp.left;
}
node.right = removeHelper(node.right, temp.val);
@@ -177,12 +153,10 @@ class AVLTree
}
/* 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)
{
while (cur != null) {
// 目标节点在 cur 的右子树中
if (cur.val < val)
cur = cur.right;
@@ -198,25 +172,21 @@ class AVLTree
}
}
public class avl_tree
{
static void testInsert(AVLTree tree, int val)
{
public class avl_tree {
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)
{
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);
}
[Test]
public void Test()
{
public void Test() {
/* 初始化空 AVL 树 */
AVLTree avlTree = new AVLTree();

55
codes/csharp/chapter_tree/binary_search_tree.cs
View File

@@ -9,25 +9,21 @@ using NUnit.Framework;
namespace hello_algo.chapter_tree;
class BinarySearchTree
{
class BinarySearchTree {
TreeNode? root;
public BinarySearchTree(int[] nums)
{
public BinarySearchTree(int[] nums) {
Array.Sort(nums); // 排序数组
root = buildTree(nums, 0, nums.Length - 1); // 构建二叉搜索树
}
/* 获取二叉树根节点 */
public TreeNode? getRoot()
{
public TreeNode? getRoot() {
return root;
}
/* 构建二叉搜索树 */
public TreeNode? buildTree(int[] nums, int i, int j)
{
public TreeNode? buildTree(int[] nums, int i, int j) {
if (i > j) return null;
// 将数组中间节点作为根节点
int mid = (i + j) / 2;
@@ -39,12 +35,10 @@ class BinarySearchTree
}
/* 查找节点 */
public TreeNode? search(int num)
{
public TreeNode? search(int num) {
TreeNode? cur = root;
// 循环查找，越过叶节点后跳出
while (cur != null)
{
while (cur != null) {
// 目标节点在 cur 的右子树中
if (cur.val < num) cur = cur.right;
// 目标节点在 cur 的左子树中
@@ -57,14 +51,12 @@ class BinarySearchTree
}
/* 插入节点 */
public void insert(int num)
{
public void insert(int num) {
// 若树为空，直接提前返回
if (root == null) return;
TreeNode? cur = root, pre = null;
// 循环查找，越过叶节点后跳出
while (cur != null)
{
while (cur != null) {
// 找到重复节点，直接返回
if (cur.val == num) return;
pre = cur;
@@ -76,8 +68,7 @@ class BinarySearchTree
// 插入节点 val
TreeNode node = new TreeNode(num);
if (pre != null)
{
if (pre != null) {
if (pre.val < num) pre.right = node;
else pre.left = node;
}
@@ -85,14 +76,12 @@ class BinarySearchTree
/* 删除节点 */
public void remove(int num)
{
public void remove(int num) {
// 若树为空，直接提前返回
if (root == null) return;
TreeNode? cur = root, pre = null;
// 循环查找，越过叶节点后跳出
while (cur != null)
{
while (cur != null) {
// 找到待删除节点，跳出循环
if (cur.val == num) break;
pre = cur;
@@ -104,27 +93,21 @@ class BinarySearchTree
// 若无待删除节点，则直接返回
if (cur == null || pre == null) return;
// 子节点数量 = 0 or 1
if (cur.left == null || cur.right == null)
{
if (cur.left == null || cur.right == null) {
// 当子节点数量 = 0 / 1 时， child = null / 该子节点
TreeNode? child = cur.left != null ? cur.left : cur.right;
// 删除节点 cur
if (pre.left == cur)
{
if (pre.left == cur) {
pre.left = child;
}
else
{
} else {
pre.right = child;
}
}
// 子节点数量 = 2
else
{
else {
// 获取中序遍历中 cur 的下一个节点
TreeNode? tmp = cur.right;
while (tmp.left != null)
{
while (tmp.left != null) {
tmp = tmp.left;
}
// 递归删除节点 tmp
@@ -135,11 +118,9 @@ class BinarySearchTree
}
}
public class binary_search_tree
{
public class binary_search_tree {
[Test]
public void Test()
{
public void Test() {
/* 初始化二叉搜索树 */
int[] nums = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
BinarySearchTree bst = new BinarySearchTree(nums);

6
codes/csharp/chapter_tree/binary_tree.cs
View File

@@ -9,11 +9,9 @@ using NUnit.Framework;
namespace hello_algo.chapter_tree;
public class binary_tree
{
public class binary_tree {
[Test]
public void Test()
{
public void Test() {
/* 初始化二叉树 */
// 初始化节点
TreeNode n1 = new TreeNode(1);

12
codes/csharp/chapter_tree/binary_tree_bfs.cs
View File

@@ -9,19 +9,16 @@ using NUnit.Framework;
namespace hello_algo.chapter_tree;
public class binary_tree_bfs
{
public class binary_tree_bfs {
/* 层序遍历 */
public List<int> levelOrder(TreeNode root)
{
public List<int> levelOrder(TreeNode root) {
// 初始化队列，加入根节点
Queue<TreeNode> queue = new();
queue.Enqueue(root);
// 初始化一个列表，用于保存遍历序列
List<int> list = new();
while (queue.Count != 0)
{
while (queue.Count != 0) {
TreeNode node = queue.Dequeue(); // 队列出队
list.Add(node.val); // 保存节点值
if (node.left != null)
@@ -33,8 +30,7 @@ public class binary_tree_bfs
}
[Test]
public void Test()
{
public void Test() {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode? root = TreeNode.ListToTree(new List<int?> { 1, 2, 3, 4, 5, 6, 7 });

15
codes/csharp/chapter_tree/binary_tree_dfs.cs
View File

@@ -9,13 +9,11 @@ using NUnit.Framework;
namespace hello_algo.chapter_tree;
public class binary_tree_dfs
{
public class binary_tree_dfs {
List<int> list = new();
/* 前序遍历 */
void preOrder(TreeNode? root)
{
void preOrder(TreeNode? root) {
if (root == null) return;
// 访问优先级：根节点 -> 左子树 -> 右子树
list.Add(root.val);
@@ -24,8 +22,7 @@ public class binary_tree_dfs
}
/* 中序遍历 */
void inOrder(TreeNode? root)
{
void inOrder(TreeNode? root) {
if (root == null) return;
// 访问优先级：左子树 -> 根节点 -> 右子树
inOrder(root.left);
@@ -34,8 +31,7 @@ public class binary_tree_dfs
}
/* 后序遍历 */
void postOrder(TreeNode? root)
{
void postOrder(TreeNode? root) {
if (root == null) return;
// 访问优先级：左子树 -> 右子树 -> 根节点
postOrder(root.left);
@@ -44,8 +40,7 @@ public class binary_tree_dfs
}
[Test]
public void Test()
{
public void Test() {
/* 初始化二叉树 */
// 这里借助了一个从数组直接生成二叉树的函数
TreeNode? root = TreeNode.ListToTree(new List<int?> { 1, 2, 3, 4, 5, 6, 7 });