左右置换,递归左右节点
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
public TreeNode invertTree(TreeNode root) {
if (root != null) {
TreeNode tmpNode = root.left;
root.left = root.right;
root.right = tmpNode;
invertTree(root.left);
invertTree(root.right);
}
return root;
}
}