#include <stdio.h>

int gcd ( int m , int n );

int main ( void ) {
	int x , y;
	scanf ( "%d %d" , &x , &y );
	printf ( "%d\n" , gcd ( x , y ) );
	return 0;
}

int gcd ( int m , int n ) {
	if ( n == 0 ) return m;
	return gcd ( n , m % n );
}