#define int long long
using namespace std;


int gcd(int a,int b){
	if(b==0){
		return a;
	}else{
		return gcd(b,a%b);
	}
}

signed main()
{
	
	int a,b;
	cin>>a>>b;
	cout<<gcd(a,b); 
	return 0;
}