#pragma GCC optimize("O3") #include <iostream> #include <iomanip> #include <cstdio> #include <string> #include <cstring> #include <deque> #include <list> #include <queue> #include <stack> #include <vector> #include <utility> #include <algorithm> #include <map> #include <set> #include <complex> #include <cmath> #include <limits> #include <cfloat> #include <climits> #include <ctime> #include <cassert> #include <numeric> #include <fstream> #include <functional> #include <bitset> using namespace std; using ll = long long; using P = pair<int, int>; using T = tuple<int, int, int>; template <class T> inline T chmax(T &a, const T b) {return a = (a < b) ? b : a;} template <class T> inline T chmin(T &a, const T b) {return a = (a > b) ? b : a;} constexpr int MOD = 1e9 + 7; constexpr int inf = 1e9; constexpr long long INF = 1e18; #define all(a) (a).begin(), (a).end() int dx[] = {1, 0, -1, 0}; int dy[] = {0, 1, 0, -1}; const int MAX_N = 100010; bool isPrime[MAX_N]; void eratosthenes(int n){ for(int i=0; i<=n; i++) isPrime[i] = true; isPrime[0] = false, isPrime[1] = false; for(int i=2; i*i<=n; i++){ if(isPrime[i]){ for(int j=2; i*j<=n; j++){ isPrime[i*j] = false; } } } } vector<ll> prime_factorization(ll n){ vector<ll> v; ll num = n; for(ll i=2; i*i<=n; i++){ while(num % i == 0){ num /= i; v.emplace_back(i); } } if(num != 1){ v.emplace_back(num); } return v; } int main(){ cin.tie(0); ios::sync_with_stdio(false); int n, k; cin>>n>>k; auto np = prime_factorization(n); map<int, int> npcnt; for(auto i:np){ npcnt[i]++; } int ma = 0; int ans = 0; for(int m=1; m<n; m++){ auto mp = prime_factorization(m); map<int, int> mpcnt; for(auto i:mp){ mpcnt[i]++; } int cnt = 0, div = 1; for(auto i:mpcnt){ cnt += min(i.second, npcnt[i.first]); div *= i.second + 1; } if(k <= cnt){ if(ma < div){ ma = div; ans = m; } } } cout << ans << endl; return 0; }