剑指offer(三十四)之二叉树的镜像

<span style="font-size:18px;">/**
public class TreeNode {
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;

    public TreeNode(int val) {
        this.val = val;

    }

}
*/
public class Solution {
    public void Mirror(TreeNode root) {
        if(root==null){
            return ;
        }
        TreeNode temp;
        temp=root.left;
        root.left=root.right;
        root.right=temp;
        Mirror(root.left);
        Mirror(root.right);
    }
}</span>

<span style="font-size:18px;">import java.util.*;
public class Solution {
    public void Mirror(TreeNode root) {
        if(root==null){
            return ;
        }
        Stack<TreeNode> stack=new Stack<TreeNode>();
        stack.push(root);
        while(!stack.isEmpty()){
            TreeNode node=stack.pop();
            if(node.left!=null||node.right!=null){
                TreeNode temp=node.left;
                node.left=node.right;
                node.right=temp;
            }
            if(node.left!=null){
                stack.push(node.left);
            }
            if(node.right!=null){
                stack.push(node.right);
            }
        }
    }
}</span>