Leetcode 572 另一个树的子树 ： 递归转换为判断树是否相同

递归转化为判断两个二叉树是否相同

1class Solution {
2public:
3    bool isSubtree(TreeNode* s, TreeNode* t) {
4        if(s==NULL) return false;
5        if(t==NULL) return true;
6        return isSubtree(s->left,t) || isSubtree(s->right,t) || isSameTree(s,t);
7    }
8
9    bool isSameTree(TreeNode* s, TreeNode* t){
10        if(s==NULL&&t==NULL) return true;
11        else if(s==NULL||t==NULL) return false;
12        else if(s->val==t->val) return isSameTree(s->left,t->left) && isSameTree(s->right,t->right);
13        else return false;
14    }
15};