[LeetCode] 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.
/**
* Definition for binary tree
* 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) {
// Note: The Solution object is instantiated only once and is reused by each test case.
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 )
return false;
else
return isSameTree( p->left, q->left ) && isSameTree( p->right, q->right );
}
};
思路：简单递归
