import java.util.Scanner; public class N067 { static double max=Integer.MAX_VALUE,min=Math.pow(10, -9),k; static int n; static int[] l; public static void main(String[] args) { Scanner sc = new Scanner(System.in); n=sc.nextInt(); l=new int[n]; for(int i=0;i=k) {break;} } if(cnt>=k) { min=av; } else { max=av; } } System.out.printf("%.8f",av); } }