标签:leetcode
Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).
For example, this binary tree is symmetric:
1 / 2 2 / \ / 3 4 4 3
But the following is not:
1 / 2 2 \中文:给定一二叉树,检查它是否是它自己的镜像(例如,以中心对称)。3 3
递归:
public boolean isSymmetric(TreeNode root) { if(root == null) return true; return isSymmetric(root,root); } public boolean isSymmetric(TreeNode left,TreeNode right) { if(left == null && right == null) return true; else if(left == null || right == null) return false; return left.val == right.val && isSymmetric(left.left,right.right) && isSymmetric(left.right,right.left); }
LeetCode——Symmetric Tree,布布扣,bubuko.com
标签:leetcode
原文地址:http://blog.csdn.net/laozhaokun/article/details/30271621