import java.util.*;
public class GCD {
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
int divident =sc.nextInt();
int divisor =sc.nextInt();
int rem;
while(divident/divisor != 0)
{
rem=divident % divisor;
divident=divisor;
divisor=rem;
}
System.out.println(divisor);
}
}