Given two binary trees, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally identical and the nodes have the same value. Example 1: Input: / \ / \ [,,], [,,] Output: true Example 2:…

Input: 1 1 / \ / \ 2 3 2 3 [1,2,3], [1,2,3] Output: true Example 2: Input: 1 1 / \ 2 2 [1,2], [1,null,2] Output: false Example 3: Input: 1 1 / \ / \ 2 1 1 2 [1,2,1], [1,1,2] Output: false 判断两个二叉树是否相等. 一:使用递归. public boolean isSameTree(TreeNode p, Tre…

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).For example, this binary tree [1,2,2,3,4,4,3] is symmetric:    1   / \  2   2 / \   / \3  4 4  3 But the following [1,2,2,null,3,null,3] is not:    1   / \ …

dfs遍历一下判断 public boolean isSameTree(TreeNode p, TreeNode q) { if (p==null) { return q == null; } else { if (q==null || p.val!=q.val) return false; else { return (isSameTree(p.left,q.left)&&isSameTree(p.right,q.right)); } } }…

Given two binary trees, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally identical and the nodes have the same value. Example 1: Input: 1 1 / \ / \ 2 3 2 3 [1,2,3], [1,2,3] Outpu…

就是判断两棵树的值和结构是否相同 注意:要判断是否所有的树节点是否为NULL /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: bool isSameTre…

1 题目描述 输入两棵二叉树A,B,判断B是不是A的子结构.(ps:我们约定空树不是任意一个树的子结构) 2 思路和方法 (1)先在A中找和B的根节点相同的结点 (2)找到之后遍历对应位置的其他结点,直到B中结点遍历完,都相同时,则B是A的子树 (3)对应位置的结点不相同时,退出继续在A中寻找和B的根节点相同的结点,重复步骤,直到有任何一棵二叉树为空退出 3 C++核心代码 3.1 递归实现1 /* struct TreeNode { int val; struct TreeNode *left…

Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value. 给出两个二叉树,写一个方法判断两个二叉树是否相等, 如果两个二叉树相等,说明结构相同并且每个节点的值相同. 如果两个节点都为空,则说…

Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value. 判断两棵树是否相同. 很简单.递归. /** * Definition for a binary tree node. * publ…

Invert a binary tree 翻转一棵二叉树 假设有如下一棵二叉树: 4  / \   2    7  / \   / \ 1  3 6  9翻转后: 4     /    \    7     2   / \    / \  9  6  3  1 这里采用递归的方法来处理.遍历结点,将每个结点的两个子结点交换位置即可. 从左子树开始,层层深入,由底向上处理结点的左右子结点:然后再处理右子树 全部代码如下: public class InvertBinaryTree { public…