leetcode - Same Tree

 1 #include <stddef.h>
 2 /*
 3 struct TreeNode
 4 {
 5     int val;
 6     TreeNode *left;
 7     TreeNode *right;
 8     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 9 };
10 */
11 class Solution
12 {
13 public:
14     bool isSameTree(TreeNode *p, TreeNode *q)
15     {
16         //p,q均为空
17         if (p == NULL && q == NULL)
18         {
19             return true;
20         }
21 
22         //p,q不为空时，p,q指向结点的值相同且p,q左右子树均相同，则说明p,q指向的树相同
23         if (p != NULL && q != NULL && p->val == q->val && isSameTree(p->left, q->left) && isSameTree(p->right, q->right))
24         {
25             return true;
26         }
27 
28         return false;
29     }
30 };