public boolean isSameTree(TreeNode p, TreeNode q){
		
		if(p == null && q == null){
			return true;
		}
		
		if(p == null && q != null){
			return false;
		}
		
		if(p != null && q == null){
			return false;
		}
		
		if(p.val == q.val){
			return true && isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
		}
		
		return false;
	}