dfs递归遍历二叉树,从底向上依次交换各个节点的左右子节点,生成镜像二叉树
public class Solution {
public TreeNode Mirror (TreeNode pRoot) {
// write code here
if(pRoot==null || (pRoot.left==null&&pRoot.right==null))
return pRoot;
TreeNode left = Mirror(pRoot.left);
TreeNode right = Mirror(pRoot.right);
pRoot.right = left;
pRoot.left = right;
return pRoot;
}
}