> #include<iostream>
> 
> using namespace std;
> 
> int main()
> {
> 	int N, M, P, C;
> 	cin >> N >> M >> P >> C;
> 
> 	while( N + M + P + C != 0 )
> 	{
> 		if( P > M ) //The fake money given to the boss is lager. 
> 			cout << C + N << endl;
> 		else // or, subtract the money the customer gived to.
> 			cout << N + P - M << endl;
> 		cin >> N >> M >> P >> C;
> 	}
> 	
> 	return 0;
> }
问题在哪里，去掉先前那个if就可以啊~？