

import java.util.Arrays;
import java.util.Scanner;

public class Main {
    static Scanner sc = new Scanner(System.in);


    public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    }
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {
    static Scanner sc = new Scanner(System.in);


    public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    }
} Main static Scanner sc = new Scanner(System.in); sc new Scanner(System.in) public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    } main {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    } int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int[] a = new int[n]; a new int[n] n for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            a[i] = sc.nextInt();
        } {
            a[i] = sc.nextInt();
        } a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc Arrays.sort(a) Arrays.sort Arrays a double sum = a[0]; sum a[0] a 0 for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        } int i = 1; int i = 1; i 1 i < n i n i++ i++ i {
            sum = (sum + a[i]) / 2;
        } {
            sum = (sum + a[i]) / 2;
        } sum = (sum + a[i]) / 2 sum (sum + a[i]) / 2 (sum + a[i]) sum a[i] a i 2 System.out.println(sum) System.out.println System.out System System.out sum String[] args args public class Main {
    static Scanner sc = new Scanner(System.in);


    public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    }
} public class Main {
    static Scanner sc = new Scanner(System.in);


    public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    }
} Main


import java.util.Arrays;
import java.util.Scanner;

public class Main {
    static Scanner sc = new Scanner(System.in);


    public static void main(String[] args) {
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        Arrays.sort(a);
        double sum = a[0];
        for (int i = 1; i < n; i++) {
            sum = (sum + a[i]) / 2;
        }
        System.out.println(sum);
    }
}
