两个程序:
#include<stdio.h>
void main()
{
double a,b,c,res;
printf("please input three number:");
scanf("%lf%lf%lf",&a,&b,&c);
res=a*b*c;
printf("%.0lf*%.0lf*%.0lf=%.0lf\n",a,b,c,res);}
#include<stdio.h>
void main()
{
double a,b,c,d,f,g;
printf("please input two number:");
scanf("%lf%lf",&a,&b);
c=a+b;
d=a-b;
f=a*b;
g=a/b;
printf("%.0lf+%.0lf=%.0lf\n",a,b,c);
printf("%.0lf-%.0lf=%.0lf\n",a,b,d);
printf("%.0lf*%.0lf=%.0lf\n",a,b,f);
printf("%.0lf/%.0lf=%.2lf\n",a,b,g);
}