#include <stdio.h>
#define P 3.1415927
#define toFeet(x) x/12.0
#define toMiles(x) x/5280.0
int main(){
double diameter;//直径
int revolutions;//转数
double time;//时间
double s;
int count=1;
while(scanf("%lf%d%lf",&diameter,&revolutions,&time),revolutions){
time/=3600;
diameter/=63360;
s=diameter*P*revolutions;
printf("Trip #%d: %.2lf %.2lf\n",count++,s,s/time);
}
}
原文：http://www.cnblogs.com/wangkun1993/p/6286408.html