实验4

#include<stdio.h>
int main(void)
{
    double r,h,v,n;
    printf("Enter r,h and n ");
    scanf("%lf%lf%lf",&r,&h,&n);
    if(r<=0||h<=0)
    {
        printf("输入错误，重新输入");
    }
    else{
        v=cylinder(r,h,n);
        printf("v=%.3f\n",v);
    }
    return 0;
}
double cylinder(double r,double h,double n)
{
    double result;

    result=3.1415926*r*r*h*n;

    return result;
}