#include <iostream>
#include <fstream>
using namespace std;
int main ()
{  unsigned int a,b;
   ifstream fin("cmmdc.in");
   fin>>a>>b;
   ofstream fout("cmmdc.out");
   while(a){
    int remainder=a%b;
    a=b;
    b=remainder;
     }
   fout<<remainder;


    return 0;
}