已经傻了,弄了小半天了,感觉自己能搜的都搜了yi'bian
#include "pch.h"
#include "stdio.h"
void main()
{
float a, b;
char c;
printf("input expression:a+(-,*,/)b\n");
scanf_s("%lf%c%lf", &a,&c,&b,128,128,128);
switch (c)
{
case '+':
printf("%lf\n", a + b);
break;
case '-':
printf("%lf\n", a - b);
break;
case '*':
printf("%lf\n", a * b);
break;
case '/':
printf("%lf\n", a / b);
break;
}
}