100. Same Tree

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.

 

递归遍历左子树和右子树

/*** 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 isSameTree(TreeNode* p, TreeNode* q) {if (p == NULL && q == NULL) return true;if (p == NULL && q != NULL) return false;if (p != NULL && q == NULL) return false;if (p->val == q->val) {bool x = isSameTree(p->left, q->left);bool y = isSameTree(p->right, q->right);return x&&y;}return false;}
};