#include <stdio.h>

unsigned int a, b, rest;
int main (void)
{
    FILE *fin=fopen("cmmdc.in", "r");
    FILE *fout=fopen("cmmdc.out", "w");
    fscanf(fin, "%d %d", &a, &b);
    fclose(fin);
    while(b)
    {
        rest=a%b;
        a=b;
        b=rest;
    }
    if(a==1)
		fprintf(fout, "0");
    else fprintf(fout, "%d", a);
    fclose(fout);
    return 0;
}