1.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.
2.题目要求:判断两个二叉树是否相等。
3.方法:检查当前节点的左右节点是否相同,然后递归检查左子树和右子树。
4.代码:
/**
- 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) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
if (p == NULL && q == NULL)
return true;
else if (p == NULL || q == NULL)
return false;
return p->val == q->val && isSameTree(p->left, q->left)
&& isSameTree(p->right, q->right);
}
};