题解 | #简单计算器#

#include<stdio.h>
int main(){
double a, b;
char ch;
while ((scanf("%lf%c%lf", &a, &ch, &b)) != EOF)
{
    if (ch == '+' || ch == '-' || ch == '*' || ch == '/')
    {
        switch (ch)
        {
        case '+':printf("%.4lf%c%.4lf=%.4lf", a, ch, b, a + b); break;
        case '-':printf("%.4lf%c%.4lf=%.4lf", a, ch, b, a - b); break;
        case '*':printf("%.4lf%c%.4lf=%.4lf", a, ch, b, a * b); break;
        case '/':if (b == 0.0){
                printf("Wrong!Division by zero!"); break;
            }else{
                printf("%.4lf%c%.4lf=%.4lf", a, ch, b, a / b); break;
            }
        }
    }
    else
        printf("Invalid operation!");
}
return 0;
}