100. 相同的树
解法1:
1 /** 2 * Definition for a binary tree node. 3 * struct TreeNode { 4 * int val; 5 * TreeNode *left; 6 * TreeNode *right; 7 * TreeNode(int x) : val(x), left(NULL), right(NULL) {} 8 * }; 9 */ 10 class Solution { 11 public: 12 bool isSameTree(TreeNode* p, TreeNode* q) 13 { 14 if(!p && !q) return true; 15 if(!p || !q) return false; 16 if(p->val != q->val) return false; 17 else 18 return isSameTree(p->left, q->left) && isSameTree(p->right, q->right); 19 } 20 };