GCD

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GreaterCommonDivider
{
    class GreaterCommonDivider
    {
        static void Main(string[] args)
        {
            int firstNumber = int.Parse(Console.ReadLine());
            int secondNumber = int.Parse(Console.ReadLine());

            var maxDiff = int.MinValue;

            for(int i = 1; i <= Math.Min(firstNumber , secondNumber); i++)
            {
                if(firstNumber % i == 0 && secondNumber % i == 0 && i > maxDiff)
                {
                    maxDiff = i;
                }
            }

            Console.WriteLine(maxDiff);

            int a = int.Parse(Console.ReadLine());
            int b = int.Parse(Console.ReadLine());

            while(a != b)
            {
                if(a > b)
                {
                    a = a - b;
                }
                else
                {
                    b = b - a;
                }
            }
            Console.WriteLine(a);

            //Secon solution
            //while (b!=0)
            //{
            //    var tmp = b;
            //    b = a % b;
            //    a = tmp;
            //}
            //Console.WriteLine(a);
        }
    }
}