//**********************************************************
// Program Name: poundstokg.java                           *
// Author: Pat Moss                                        *
// Date: Sept 26, 2005  Rev: 01                            *
//                                                         *
// Convert input Pounds to Kilograms to two decimal places *
//**********************************************************

import java.util.Scanner;
import java.text.DecimalFormat;

public class poundstokg
{
 public static void main (String[] args)
 {
  final double POUNDSTOKG = 0.453592;   // 1 pound = 0.453592 kg

  double inputpounds = 0.0;
  double kilograms = 0.0;

  // Round the output value to two decimal places
  DecimalFormat fmt = new DecimalFormat ("0.##");

  Scanner scan = new Scanner(System.in);

  System.out.println ("poundstokg.java by pat moss");
  System.out.println ("");

  System.out.print ("Enter a positive double value for pounds (0 to quit): ");
  inputpounds = scan.nextDouble();

  while (inputpounds != 0)  // Use the sentinel value of 0 to terminate the loop
  {
   if(inputpounds < 0)
   {
    System.out.println ("Invalid input value. Please reenter a positive double value.");
   }
   else
   {
    kilograms = POUNDSTOKG * inputpounds;

    System.out.print ("The equivalent weight in kg is ");
    System.out.print (fmt.format(kilograms));
    System.out.println ("");
   }

   System.out.println ("");
   System.out.print ("Enter a positive double value for pounds (0 to quit): ");
   inputpounds = scan.nextDouble();
  }

  System.out.println ("All Done...");

 }
}