C++实现计算器

#include<stdio.h>
#include<iostream>
using namespace std;
int main()
{
    int a,b,c;
    char op;
    cin >> a ;
    cin >> b;
    cin >> op;
    switch (op){
        case ‘+‘:
            c = a + b;
            break;
        case ‘-‘:
            c = a - b;
            break;
        case ‘*‘:
            c = a * b;
            break;
        case ‘/‘:
            c = a / b;
            break;
        default:
            c = 0;
            break;
    }
    printf("%d", c);
    system("pause");
    return 0;
}