// goodwincommaderek@gmail.com
import java.util.Scanner;

public class memoriesofpassportstamps_dg_ac {
    public static void main(String[] args) {

        // input
        Scanner in = new Scanner(System.in);
        int N = in.nextInt();
        long K = in.nextLong();
        long[] ps = new long[N];
        for(int n=0;n<N;n++) {
            ps[n] = in.nextLong();
        }

        // binary search
        long lo = 0, hi = 1_000_000_000_000_000_000L;
        while(lo + 1 < hi) {
            long mid = lo + (hi-lo) / 2;
            long totalTrips = 0;
            for(int n=0;n<N;n++) {

                // split this contiguous subsection of passport between this many trips,
                // given that mid is our guess for max
                totalTrips += (ps[n]-1) / mid + 1;
            }
            // some of your trips can be stampless; that's OK.
            if (totalTrips <= K) {
                // mid is high enough that it could work
                hi = mid;
            } else {
                lo = mid;
            }
        }
        System.out.println(hi);
    }
}