CalculateGCD

using System;

    class CalcilateGCD
    {
        static void Main()
        {
            Console.Write("Enter your first integer number: ");
            int first = int.Parse(Console.ReadLine());
            Console.Write("Enter your second integer number: ");
            int second = int.Parse(Console.ReadLine());

            while (first != 0 && second != 0)
            {
                if (first > second)
                {
                    first -= second;
                }
                else
                {
                    second -= first;
                }
            }

            Console.WriteLine(Math.Max(first,second));

        }
    }