using System;

public class Program

{

    public static void Main()

    {

        int beg = 1;

        long number = 1;

        while (beg < 11)

        {

            number *= beg;

            beg++;

        }

        Console.WriteLine("The product of the first 10 numbers is: " + number);

        while (beg < 21)

        {

            number *= beg;

            beg++;

        }

        Console.WriteLine("The product of the first 20 numbers is: " + number);

        while (beg < 51)

        {

            number *= beg;

            beg++;

        }

        Console.WriteLine("The product of the first 50 numbers is: " + number);

        while (beg < 101)

        {

            number *= beg;

            beg++;

        }

        Console.WriteLine("The product of the first 100 numbers is: " + number);

        while (beg < 1001)

        {

            number *= beg;

            beg++;

        }

        Console.WriteLine("The product of the first 1000 numbers is: " + number);

    }

}