解题思路:
(1)注意这里的树的子结构和剑指offer里面定义的不一样
(2)这里指的是以某个节点作为根结点,剩下的所有点值均相同,也就是说一直到最后的叶子结点
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
bool isSubtree(TreeNode* s, TreeNode* t) {
if(s==NULL || t==NULL) return false;
else return comp(s,t)||isSubtree(s->left,t)||isSubtree(s->right,t);
}
bool comp(TreeNode* s, TreeNode* t) {
if(s==NULL && t==NULL) return true;
if(s==NULL || t==NULL) return false;
if(s->val!=t->val) return false;
else return comp(s->left,t->left)&&comp(s->right,t->right);
}
};