程序代码：

#include<stdio.h>
#define PI 3.14159
int Cheng(long a)
{
    return(PI*a*a);
}
int Zhou(long b)
{
    return(2*PI*b);
}
main()
{
    long R;
    int aaa ,bbb ;
    printf("Please input a number:");
    scanf("%f",&R);
    aaa=Cheng(R);
    bbb=Zhou(R);
    printf("aaa=%.15f\n",aaa);
    printf("bbb=%.15f\n",bbb);
}

程序代码：

#include<stdio.h>
#define PI 3.141592654
double Cheng(double a)
{
    return(PI*a*a);
}
double  Zhou(double b)
{
    return(2*PI*b);
}
main()
{
    double R;
    double aaa ,bbb ;
    printf("Please input a number:");
    scanf("%lf",&R);
    aaa=Cheng(R);
    bbb=Zhou(R);
    printf("aaa=%.15f\n",aaa);
    printf("bbb=%.15f\n",bbb);
}