#include #include #include #include using namespace std; typedef long long ll; vector p; bool isprime[100001]; ll findprime(ll a) { for (int i = 0; i < p.size()&&p[i]*p[i]<=a; i++) { if (a%p[i] == 0) return p[i]; } return a; } int main() { for (int i = 0; i <= 100000; i++) isprime[i] = true; isprime[0] = isprime[1] = false; for (int i = 2; i <= 100000; i++) { if (!isprime[i]) continue; p.push_back(i); for (int j = 2 * i; j <= 100000; j += i) isprime[j] = false; } ll l, h; cin >> l >> h; ll ans = 1, out = 1; for (ll big = ceil(sqrt(h)); big >= ans; big--) { cout << big << endl; if (!isprime[big]) continue; for (ll another = h / big; another*big >= l; another--) { // cout << big << " " << another; ll small=min(big,findprime(another)); if (ans < small) ans = small, out = another*big; else if (ans == small) out = max(out, another*big); // cout << " " << ans << " " << out << endl; } } cout << out << endl; return 0; }