比较根节点,然后比较左子树,然后是右子树。
如果p为空且q为空则true,如果p不为空且q不为空,比较pq的值和左子树右子树,其他情况都是false
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
bool isSameTree(TreeNode* p, TreeNode* q) {
if(p == NULL && q == NULL)
return true;
if(p != NULL && q != NULL)
return p->val == q->val && isSameTree(p->left,q->left) && isSameTree(p->right, q->right);
else
return false;
}
};
再少几行:
bool isSameTree(TreeNode *p, TreeNode *q) {
if (p == NULL || q == NULL) return (p == q);
return (p->val == q->val && isSameTree(p->left, q->left) && isSameTree(p->right, q->right));
}