杭电ACM1.2.1   Biker's Trip Odometer

http://acm.hdu.edu.cn/game/entry/problem/show.php?chapterid=1&sectionid=2&problemid=2

1 //author:pz 2  3 import java.text.DecimalFormat; 4 import java.util.Scanner; 5  6 public class Main{ 7     final double PI =  3.1415927; 8     final int InchesPerFoot = 12; 9     final int FeetPerMile = 5280;10     final int SecondsPerMinute = 60;11     final int MinutesPerHour = 60;12 13     double diameter;14     int revolutions;15     double time;16     double distance;17     double mph;18     19     static int count = 1;20 21     Main(double diameter, int revolutions, double time){22         this.diameter = diameter;23         this.revolutions = revolutions;24         this.time = time;        25     }26     27     void calculate(){28         DecimalFormat df = new DecimalFormat("0.00");//这里如果写 #.00 将会通不过。。。郁闷了很长时间29         double perimeter = PI * diameter;30         double inchesDistance = perimeter * revolutions;31         double feetDistance = inchesDistance / InchesPerFoot;32         distance = feetDistance / FeetPerMile;33         double minuteTime = time / SecondsPerMinute;34         double hourTime = minuteTime / MinutesPerHour;35         mph = distance / hourTime;36         System.out.println("Trip #" + count + ": " + df.format(distance) + " " + df.format(mph));37         count ++;38     }39     40     public static void main(String args[]){41         Scanner scan = new Scanner(System.in);42         while(scan.hasNext()){43             double diameter = scan.nextDouble();44             int revolutions = scan.nextInt();45             if(revolutions == 0)46                 break;47             double time = scan.nextDouble();48             Main trip = new Main(diameter, revolutions, time);49             trip.calculate();            50         }51     }52 }