#include <iostream>

using namespace std;
int main()
{
    int n;
    cin >> n;
    
    long long K;
    cin >> K;
    
    int niza[n];
    for(int i = 0; i < n; i++) {
        cin >> niza[i];
    }
    
    long long L = 1;
    long long R = 40000000000000;
    long long result = 40000000000000;
    while(L <= R) {
        long long middle = (L + R) / 2;
        
        long long resheni_zadaci = 0;
        for(int i = 0; i < n; i++) {
            resheni_zadaci += (middle / niza[i]);
        }
        if(resheni_zadaci >= K) {
            R = middle - 1;
            result = min(result, middle);
        }
        else {
            L = middle + 1;
        }
    }
    cout << result << endl;
    
    return 0;
}