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.
题解：采取递归的方式，对结点进行判断。
/** * 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; else if(p==NULL&&q!=NULL) return false; else if(p!=NULL&&q==NULL) return false; else if(p!=NULL&&q!=NULL&&p->val!=q->val) return false; else { return isSameTree(p->left,q->left)&&isSameTree(p->right,q->right); } } };
原文：http://www.cnblogs.com/fengxw/p/6082864.html