题解 | #简单计算器#

#include <stdio.h>
int calculate(double a,double b,char op)
{
    double result;
    switch(op)
    {
        case '*':result=a*b;printf("%.4lf%c%.4lf=%.4lf\n",a,op,b,result);break;
        case '/':result=a/b;printf("%.4lf%c%.4lf=%.4lf\n",a,op,b,result);break;
        case '+':result=a+b;printf("%.4lf%c%.4lf=%.4lf\n",a,op,b,result);break;
        case '-':result=a-b;printf("%.4lf%c%.4lf=%.4lf\n",a,op,b,result);break;
        default:printf("Invalid operation!\n");break;
    }
    return result;
}
int main() 
{
    char m;
    double a,b;
    scanf("%lf %c %lf",&a,&m,&b);
    if(m=='/'&&b==0) printf("Wrong!Division by zero!\n");
    else  calculate(a,b,m);
    return 0;
}