/*
* Auhtor : Prince Of Persia
* email : ali.bhz@gmail.com
*/
#include<iostream>
using namespace std;
int m(int a,int b)
{
if(a < b)
return m(b,a);
else if (b == 0)
return a;
else
return m(b, (a % b) );
}
int main()
{
int a = 20;
int b = 28;
cout << m(a,b);
return 1;
}