import java.util.Collections;
import java.util.LinkedList;
import java.util.Scanner;

public class Main {

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

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  }
} import java.util.Collections; Collections java.util import java.util.LinkedList; LinkedList java.util import java.util.Scanner; Scanner java.util public class Main {

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

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  } main {
    Scanner sc = new Scanner(System.in);

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc LinkedList<Double> v = new LinkedList<>(); v new LinkedList<>() for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
      v.add(sc.nextDouble());
    } {
      v.add(sc.nextDouble());
    } v.add(sc.nextDouble()) v.add v sc.nextDouble() sc.nextDouble sc Collections.sort(v) Collections.sort Collections v while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    } v.size() > 1 v.size() v.size v 1 {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    } double a = v.poll(); a v.poll() v.poll v double b = v.poll(); b v.poll() v.poll v v.addFirst((a + b) / 2.0) v.addFirst v (a + b) / 2.0 (a + b) a b 2.0 System.out.println(v.get(0)) System.out.println System.out System System.out v.get(0) v.get v 0 String[] args args public class Main {

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

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  }
} public class Main {

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

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  }
} Main
import java.util.Collections;
import java.util.LinkedList;
import java.util.Scanner;

public class Main {

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

    int N = sc.nextInt();

    LinkedList<Double> v = new LinkedList<>();
    for (int i = 0; i < N; i++) {
      v.add(sc.nextDouble());
    }

    Collections.sort(v);

    while (v.size() > 1) {
      double a = v.poll();
      double b = v.poll();
      v.addFirst((a + b) / 2.0);
    }

    System.out.println(v.get(0));
  }
}