Balloon Comes!（模拟计算器）

#include<iostream>
using namespace std;

int main(){
	int T,flag;
	char c;
	int a, b;
	cin >> T;
	while (T--){
		cin >> c >> a >> b;
		switch (c)
		{
		case '+':cout << a + b << "\n"; break;
		case '-':cout << a - b << "\n"; break;
		case '*':cout << a*b << "\n"; break;
		case '/': flag = a % b == 0 ? 0 : 1;
			if (flag) printf("%.2f\n", (double)a / (double)b);
			else cout << a / b << "\n";
		default:
			break;
		}

	}
	return 0;
}