Java算法_ 反转二叉树(LeetCode_Hot100)

题目描述：给你一棵二叉树的根节点 ，翻转这棵二叉树，并返回其根节点。root。

获得更多？算法思路:代码文档，算法解析的私得。

运行效果

完整代码

/*** 2 * @Author: LJJ* 3 * @Date: 2023/8/16 13:18* 4*/public class InvertBinaryTree {static class TreeNode {int val;TreeNode left;TreeNode right;TreeNode(int val) {this.val = val;}}public TreeNode invertTree(TreeNode root) {if (root == null) {return null;}//递归交换左右子树TreeNode temp = root.left;root.left = root.right;root.right = temp;// 递归翻转左子树和右子树invertTree(root.left);invertTree(root.right);return root;}public static void main(String[] args) {InvertBinaryTree invertBinaryTree = new InvertBinaryTree();// 构造二叉树TreeNode root = new TreeNode(4);root.left = new TreeNode(2);root.right = new TreeNode(7);root.left.left = new TreeNode(1);root.left.right = new TreeNode(3);root.right.left = new TreeNode(6);root.right.right = new TreeNode(9);System.out.print("翻转前的二叉树中序遍历结果 : ");inorderTraversal(root);// 翻转二叉树TreeNode invertedRoot = invertBinaryTree.invertTree(root);System.out.println(" ");// 打印翻转后的二叉树中序遍历结果System.out.print("翻转后的二叉树中序遍历结果 : ");inorderTraversal(invertedRoot);}// 中序遍历二叉树private static void inorderTraversal(TreeNode root) {if (root == null) {return;}inorderTraversal(root.left);System.out.print(root.val + " ");inorderTraversal(root.right);}
}