using System;

public class Program

{

    public static void Main()

    {

        int a, b;

        Console.WriteLine(" намиране на НОД");

        Console.Write(" а=" );

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

        Console.WriteLine(" b =");

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

        while ( a!=b)

        {

            if ( a > b) a=a-b;

            else b = b-a;

        }

        Console.WriteLine("НОД е" +a);

    }

}