import java.util.*; import java.io.*; public class Main{ static int N; static int[] l; static int K; public static void main(String[] args) { Scanner sc = new Scanner(System.in); N = sc.nextInt(); l = new int[N]; for(int i=0; i 1) double mid = (lb + ub) / 2; if (mid < 1e-10) { lb = mid; continue; } int sum = 0; for(int i=0; i= K) lb = mid; else ub = mid; } System.out.println(lb); } }