#include <iostream> #include <vector> #include <algorithm> #include <cmath> #include <queue> #include <string> #include <map> #include <set> #include <stack> #include <tuple> #include <deque> #include <array> #include <numeric> #include <bitset> #include <iomanip> #include <cassert> #include <chrono> #include <random> #include <limits> #include <iterator> #include <functional> #include <sstream> #include <fstream> #include <complex> #include <cstring> #include <unordered_map> #include <unordered_set> using namespace std; using ll = long long; using P = pair<int, int>; constexpr int INF = 1001001001; constexpr int mod = 1000000007; // constexpr int mod = 998244353; template<class T> inline bool chmax(T& x, T y){ if(x < y){ x = y; return true; } return false; } template<class T> inline bool chmin(T& x, T y){ if(x > y){ x = y; return true; } return false; } int main(){ ios::sync_with_stdio(false); cin.tie(nullptr); int n, m, p; cin >> n >> m >> p; vector<int> a(n), b(n), divcnt(n); int amax = 0; for(int i = 0; i < n; ++i){ cin >> a[i]; chmax(amax, a[i]); b[i] = a[i]; while(b[i] % p == 0){ b[i] /= p; divcnt[i] += 1; } } int ans = INF; for(int i = 0; i < n; ++i){ if(a[i] > m){ cout << 1 << endl; return 0; } if(b[i] == 1) continue; ll prod = 1; int sum = 0; while(prod <= m){ sum += 1; if(prod * amax > m){ prod *= amax; } else if(prod * a[i] > m){ prod *= a[i]; } else{ prod *= b[i]; sum += divcnt[i]; } } chmin(ans, sum); } if(ans == INF) ans = -1; cout << ans << endl; return 0; }