using System;

​

public class Program

{

    public static void Main(string[] args)

    {

        byte targetAge;

        byte startAge;

        int targetAmount;

        do

        {

            Console.Write("The amount you want to have at the end: ");

        }

        while (!int.TryParse(Console.ReadLine(), out targetAmount));

        do

        {

            Console.Write("Your age at the end: ");

        }

        while (!byte.TryParse(Console.ReadLine(), out targetAge));

        do

        {

            Console.Write("Your age at the beginning: ");

        }

        while (!byte.TryParse(Console.ReadLine(), out startAge));

        Console.WriteLine("\nCalculation  (5% p.a.):\n");

        PrintOverview(targetAge, startAge, targetAmount, 5);

    }

​

    static void PrintOverview(byte targetAge, byte startAge, int amount, int interestRate)

    {

        for (; targetAge >= startAge; targetAge--)

        {

            Console.WriteLine("At {0} you have to have {1} on your account", targetAge, amount);

            amount = (int)(amount / (1 + (double)interestRate / 100));

        }

    }

}