LeetCode572. 另一个树的子树

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