68 lines
1.6 KiB
Java
68 lines
1.6 KiB
Java
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//翻转一棵二叉树。
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//
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// 示例：
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//
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// 输入：
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//
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// 4
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// / \
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// 2 7
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// / \ / \
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//1 3 6 9
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//
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// 输出：
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//
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// 4
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// / \
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// 7 2
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// / \ / \
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//9 6 3 1
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//
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// 备注:
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//这个问题是受到 Max Howell 的 原问题 启发的 ：
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//
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// 谷歌：我们90％的工程师使用您编写的软件(Homebrew)，但是您却无法在面试时在白板上写出翻转二叉树这道题，这太糟糕了。
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// Related Topics 树 深度优先搜索 广度优先搜索 二叉树
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// 👍 919 👎 0
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package leetcode.editor.cn;
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import com.code.leet.entiy.TreeNode;
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//226:翻转二叉树
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public class InvertBinaryTree{
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public static void main(String[] args) {
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//测试代码
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Solution solution = new InvertBinaryTree().new Solution();
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}
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//力扣代码
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//leetcode submit region begin(Prohibit modification and deletion)
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/**
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* Definition for a binary tree node.
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* public class TreeNode {
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* int val;
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* TreeNode left;
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* TreeNode right;
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* TreeNode() {}
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* TreeNode(int val) { this.val = val; }
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* TreeNode(int val, TreeNode left, TreeNode right) {
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* this.val = val;
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* this.left = left;
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* this.right = right;
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* }
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* }
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*/
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class Solution {
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public TreeNode invertTree(TreeNode root) {
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if (root == null) {
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return null;
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}
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TreeNode left = invertTree(root.left);
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root.left = invertTree(root.right);
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root.right = left;
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return root;
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}
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}
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//leetcode submit region end(Prohibit modification and deletion)
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}
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