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=='/')
        {
            if(ch=='+')
                printf("%.4lf%c%.4lf=%.4lf\n",a,ch,b,a+b);
                else if(ch=='-')
                    printf("%.4lf%c%.4lf=%.4lf\n",a,ch,b,a-b);
            else if(ch=='*')
                printf("%.4lf%c%.4lf=%.4lf\n",a,ch,b,a*b);
            else
            {
                if(b==0.0)
                    printf("Wrong!Division by zero!\n");
                else
                    printf("%.4lf%c%.4lf=%.4lf\n",a,ch,b,a/b);
            }
        }
        else
            printf("Invalid operation!\n");
    }
    return 0;
}