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

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    }
} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    } main {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) int N = scanner.nextInt(); N scanner.nextInt() scanner.nextInt scanner double[] v = new double[N]; v new double[N] N for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        } int i = 0 ; int i = 0 ; i 0 i < N i N i++ i++ i {
            v[i] = scanner.nextDouble();
        } {
            v[i] = scanner.nextDouble();
        } v[i] = scanner.nextDouble() v[i] v i scanner.nextDouble() scanner.nextDouble scanner Arrays.sort(v) Arrays.sort Arrays v for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        } int i = 0 ; int i = 0 ; i 0 i < N - 1 i N - 1 N 1 i++ i++ i {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        } {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        } v[i + 1] = (v[i] + v[i + 1]) / 2.0 v[i + 1] v i + 1 i 1 (v[i] + v[i + 1]) / 2.0 (v[i] + v[i + 1]) v[i] v i v[i + 1] v i + 1 i 1 2.0 System.out.println(v[N - 1]) System.out.println System.out System System.out v[N - 1] v N - 1 N 1 String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    }
} Main

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

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int N = scanner.nextInt();
        double[] v = new double[N];

        for (int i = 0 ; i < N ; i++) {
            v[i] = scanner.nextDouble();
        }

        Arrays.sort(v);

        for (int i = 0 ; i < N - 1 ; i++) {
            v[i + 1] = (v[i] + v[i + 1]) / 2.0;
        }

        System.out.println(v[N - 1]);
    }
}
