#include <fstream>
#include <iostream>
using namespace std;
int main ()
{
	int x,y,i,aux=0,cmmdc=-9999,z=0;
	ifstream fin("cmmdc.in");
    ofstream fout("cmmdc.out");
	fin>>x>>y;
	if (x>y)
	{
		aux=x;
		x=y;
		y=aux;
		z=y/2;
		for(i=1;i<=z;i++)
			if(x%i==0 && y%i==0)
				cmmdc=i;
	}
	else
	{
		z=y/2;
		for(i=1;i<=z;i++)
			if(x%i==0 && y%i==0)
				cmmdc=i;
	}
	if (cmmdc==1)
	{
		fout<<0;
		fout.close ();
		fin.close ();
	}
	else
	{
		fout<<cmmdc;
		fout.close ();
		fin.close ();
	}
	return 0;
}