using System;

public class Program

{

    static void Main(string[] args){

int a = 12, b = 16;

int i, result=0;

for (i = 1; i <= a || i <= b; i++)

{

 if (a % i == 0 && b % i == 0)

 result = i;

 }

Console.WriteLine(result);

}

​

}