#include<bits/stdc++.h>
using namespace std;
long long  m,n; 

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

int main(){
	cin>>m>>n;
	cout<<gcd(m,n);
	return 0;
}



/**************************************************************
	Problem: 1335
	User: admin
	Language: C++
	Result: Wrong Answer
****************************************************************/