Problem:
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.
Analysis:
recursion
A possible answer:
/**
* 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->val != q->val || p==NULL || q==NULL)
return false;
else
return isSameTree(p->left,q->left) && isSameTree(p->right,q->right);
}
};
原文：http://www.cnblogs.com/liutianyi10/p/5540264.html