LeetCode 100. Same Tree

代码：

class Solution 
{
public:
    bool isSameTree(TreeNode *p, TreeNode *q) 
    {
    	if (p==NULL && q==NULL)    
    	{
    		return true;
    	} else if (p!=NULL && q!=NULL)
    	{
    		return p->val==q->val && isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
    	} else
    	{
    		return false;
    	}
    }
};