using System;

public class Program

{

    public static void Main()

    {

        /*

        Write a while and a for loop to calculate the product of the first 10 integer numbers starting at 1.

        Write a while and a for loop to calculate the product of the first 20 integer numbers starting at 1.

        After each loop print the parameters of the loop: starting number, ending number, and the result (product). 

        */

        long product = 1;

        int end = 10;

        for (int num = 1; //initialization

             num <= end; //test

             num++ //advance

             )

        {

            //Console.WriteLine(num);

            product *=  num;

        }        

        Console.WriteLine("The product of the first {0} numbers is {1}", end, product);

        product = 1;

        end = 20;

        for (int num = 1; //initialization

             num <= end; //test

             num++ //advance

             )

        {

            //Console.WriteLine(num);

            product *=  num;

        }        

        Console.WriteLine("The product of the first {0} numbers is {1}", end, product); 

        product = 1;

        end = 10;

        int num1 = 1;

        while (num1 <= end)

        {

            product *= num1;

            num1++;

        }

        Console.WriteLine("The product of the first {0} numbers is {1}", end, product);

        product = 1;

        end = 20;

        int num2 = 1;

        while (num2 <= end)

        {

            product *= num2;

            num2++;

        }

        Console.WriteLine("The product of the first {0} numbers is {1}", end, product);

        // 2. For the Gauss in you: Given m=1777 and n=2022, what is the sum of the numbers between m and n (both included in the sum)?

        // Add this for loop to your program above

        int m = 1777;

        int n = 2022;

        int num3 = m + 1;

        int sum = 0;

​

        while (num3 < n)

        {

            sum += num3;        

            num3++;

        }

​

        Console.WriteLine("The sum of the numbers between {0} and {1} is {2}", m, n, sum);

    }

}