import java.util.*; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); int[] pieces = new int[n]; for (int i = 0; i < n; i++) { pieces[i] = sc.nextInt(); } Arrays.sort(pieces); long k = sc.nextLong(); double min = pieces[n - 1] / (double)k; double max = pieces[n - 1] + 1; for (int i = 0; i < 10000; i++) { double m = (min + max) / 2; long count = 0; for (int j = n - 1; j >= 0 && count < k && pieces[j] >= m; j--) { count += (long)(pieces[j] / m); } if (count >= k) { min = m; } else { max = m; } } System.out.println(java.math.BigDecimal.valueOf(min).toPlainString()); } }