#include <bits/stdc++.h>
using namespace std;
#define int long long
int L, R, maxn;
int _gcd_(int a) {
	for (int i = a - 1; i >= 1; i--) {
		if (a % i == 0) return i;
	}
}
int _max_(int a, int b) {return a > b ? a : b;}
signed main() {
	cin >> L >> R;
	for (int i = L; i <= R; i++) maxn = _max_(maxn, _gcd_(i));
	cout << maxn;
	return 0;
}