import java.util.Scanner;

public class P6 {
    public static double euroRate, poundRate, yenRate, dollars, finalDollars;
    public static Scanner input = new Scanner(System.in);

    public static void main (String[] args)
    {
        char currency;

        euroRate = GetDoubleValue("Euro Rate: ");
        poundRate = GetDoubleValue("Pound Sterling Rate: ");
        yenRate = GetDoubleValue("Yen Rate: ");

        do
        {
            dollars = GetDoubleValue("Please enter the number of dollars you want to convert");
            ConvertedValues("Enter \"E\" to buy Euros, \"P\" to buy Pounds or \"Y\" to buy Yen");
        }
        while (ContinueConv("Are there more conversions to perform?"));
    }

    private static boolean ContinueConv(String prompt)
    {
        do
        {
            System.out.println(prompt);
            String s = input.nextLine();

            switch(s.toLowerCase())
            {
                case "yes":
                    return true;
                case "no":
                    return false;
            }
        }
        while(true);
    }

    private static double GetFee (double dollars)
    {
        return (dollars > 100) ? 0.05 : 0.1;
    }

    private static double Conversion(double rate, double value, double feePercent)
    {
        double fConversion = (value * rate);
        return fConversion - (fConversion * feePercent);
    }

    private static double GetDoubleValue(String prompt)
    {
        System.out.println(prompt);
        return input.nextDouble();
    }

    private static void ConvertedValues(String prompt)
    {
        while(true)
        {
            System.out.println(prompt);
            char c = input.next().toLowerCase().charAt(0);
            double fee = GetFee(dollars);

            switch(c)
            {
                case 'e':
                    finalDollars = Conversion(euroRate, dollars, fee);
                    System.out.println(dollars + " dollars = " + finalDollars + " euros");
                    return;
                case 'p':
                    finalDollars = Conversion(poundRate, dollars, fee);
                    System.out.println(dollars + " dollars = " + finalDollars + " pound sterlings");
                    return;
                case 'y':
                    finalDollars = Conversion(yenRate, dollars, fee);
                    System.out.println(dollars + " dollars = " + finalDollars + " yens");
                    return;
            }
        }
    }
}