Write a program to find GCD of 2 numbers in C#.NET

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace ConsoleApplication17

{

    class Program

    {

        static void Main()

        {

            int i, i1;

            Console.WriteLine("Enter 2 numbers to find GCD");

            i = int.Parse(Console.ReadLine());

            i1 = int.Parse(Console.ReadLine());

            int num, num1;

      

            if (i > i1)

            {

                num = i;

                num1 = i1;

            }

            else

            {

                num = i1;

                num1 = i;

            }

            int output = gcd(num, num1);

            Console.WriteLine("The GCD of {0} and {1} is {2}", i, i1, output);

            Console.Read();

        }

        private static int gcd(int num, int num1)

        {

            int rem = 5;

            while (num1 > 0)

            {

                rem = num % num1;

                if (rem == 0)

                    return num1;

                num = num1;

                num1 = rem;

            }

            return num;

        }

    }

}

Output :