LeetCode之postorderTraversal

vector<int> postorderTraversal(TreeNode *root) //Binary Tree Postorder Traversal 
	{		
		if (root==NULL)
		{return t;
		}		
		postorderTraversal(root->left);
		postorderTraversal(root->right);
		t.push_back(root->val);
		return t;
	}