LeetCode:Same Tree

Same Tree

Total Accepted: 132356 Total
Submissions: 304237 Difficulty: Easy

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.

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c++ code:

/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
bool isSam;
/*
void preOrder(TreeNode* p, TreeNode* q)
{
if(!isSam) return;
if(NULL == p && NULL == q) return;
if(NULL == p && NULL!= q || NULL != p && NULL== q)
{
isSam = false;
return;
}
if(p->val != q->val)
{
isSam = false;
return;
}
preOrder(p->left, q->left);
preOrder(p->right, q->right);
}
*/
void inOrder(TreeNode* p, TreeNode* q)
{
if(!isSam) return;
if(NULL == p && NULL == q) return;
if(NULL == p && NULL!= q || NULL != p && NULL== q)
{
isSam = false;
return;
}
inOrder(p->left, q->left);
if(p->val != q->val)
{
isSam = false;
return;
}
inOrder(p->right, q->right);
}

class Solution {
public:
bool isSameTree(TreeNode* p, TreeNode* q) {
isSam = true;
//preOrder(p,q);
inOrder(p,q);
return isSam;
}
};