Problem: Little Vasya loves orange juice very much. That's why any food and drink in his kitchen necessarily contains orange juice. There are n drinks in his fridge, the volume fraction of orange juice in the i-th drink equals pi percent.

One day Vasya decided to make himself an orange cocktail. He took equal proportions of each of the n drinks and mixed them. Then he wondered, how much orange juice the cocktail has.

Find the volume fraction of orange juice in the final drink.

Input

The first input line contains a single integer n (1 ≤ n ≤ 100) — the number of orange-containing drinks in Vasya's fridge. The second line contains n integers pi (0 ≤ pi ≤ 100) — the volume fraction of orange juice in the i-th drink, in percent. The numbers are separated by a space.

Output

Print the volume fraction in percent of orange juice in Vasya's cocktail. The answer will be considered correct if the absolute or relative error does not exceed 10  - 4.

Examples

Input

3
50 50 100


Output

66.666666666667


Input

4
0 25 50 75


Output

37.500000000000

Note

Note to the first sample: let's assume that Vasya takes x milliliters of each drink from the fridge. Then the volume of pure juice in the cocktail will equal <image> milliliters. The total cocktail's volume equals 3·x milliliters, so the volume fraction of the juice in the cocktail equals <image>, that is, 66.(6) percent.

Solution (in JAVA):

Solution:
import java.util.*;
import java.io.*;

public class Main {

    public static class Solution {

        public String YoungPhysicist() {
            Scanner input = new Scanner(System.in);
            int n = input.nextInt();

            int[] arr = new int[] { 0, 0, 0 };
            for (int i = 0; i < n; i++) {
                // String[] vecs = args.get(i).split(" ");
                int a = input.nextInt();
                int b = input.nextInt();
                int c = input.nextInt();
                arr[0] += a;
                arr[1] += b;
                arr[2] += c;
            }
            input.close();
            return (arr[0] == 0 && arr[1] == 0 && arr[2] == 0) ? "YES" : "NO";
        }

        public int BeautifulMatrix() {
            int[][] matrix = new int[5][5];
            Scanner input = new Scanner(System.in);
            int row = -1, col = -1;

            for (int i = 0; i < matrix.length; i++) {
                for (int j = 0; j < matrix[0].length; j++) {
                    matrix[i][j] = input.nextInt();
                    if (matrix[i][j] == 1) {
                        input.close();
                        return Math.abs(i - 2) + Math.abs(j - 2);
                    }
                }
            }
            input.close();
            return row + col;
        }

        public String QueueAtTheSchool() {
            Scanner input = new Scanner(System.in);
            int n = input.nextInt();
            int t = input.nextInt();
            input.nextLine();
            String queue = input.nextLine();
            char[] arr = queue.toCharArray();

            for (int k = 0; k < t; k++) {
                for (int i = 1; i < n; i++) {
                    if (arr[i] == 'B' && arr[i - 1] == 'G') {
                        arr[i] = 'G';
                        arr[i - 1] = 'B';
                    }
                }
            }

            input.close();
            return new String(arr);
        }

        public String Borze() {
            Scanner input = new Scanner(System.in);
            String str = input.nextLine();
            String sol = "";
            int n = str.length();

            for (int i = 0; i < n; i++) {
                String a = str.charAt(i) + "";
                String b = "";
                if (i < n - 1)
                    b = "" + str.charAt(i + 1);

                if (a.equals(".")) {
                    sol = sol + "0";
                } else if (a.equals("-")) {
                    i++;
                    if (b.equals(".")) {
                        sol = sol + "1";
                    } else if (b.equals("-")) {
                        sol = sol + "2";
                    }
                }
            }

            input.close();
            return sol;
        }

        public int BeautifulYear() {
            Scanner input = new Scanner(System.in);
            int year = input.nextInt();
            year++;
            while (!isUnique(year)) {
                year++;
            }

            input.close();
            return year;
        }

        public boolean isUnique(int num) {
            boolean unique = true;
            Set<Character> set = new HashSet<>();
            String str = num + "";
            for (int i = 0; i < str.length(); i++) {
                if (set.contains(str.charAt(i)))
                    return false;
                set.add(str.charAt(i));
            }
            return unique;
        }

        public String[][] lightsOut() {
            int sq = 3;
            int[][] input = new int[sq][sq];
            String[][] sol = new String[sq][sq];

            Scanner scanner = new Scanner(System.in);

            for (int i = 0; i < sq; i++) {
                for (int j = 0; j < sq; j++) {
                    sol[i][j] = "1";
                }
            }

            for (int i = 0; i < sq; i++) {
                for (int j = 0; j < sq; j++) {
                    input[i][j] = scanner.nextInt();

                    if (input[i][j] % 2 != 0) {
                        toggleAdj(sol, i, j);
                    }
                }
            }
            System.out.println("\n\n\n");
            for (int i = 0; i < sol.length; i++) {
                String a = sol[i][0];
                String b = sol[i][1];
                String c = sol[i][2];
                System.out.println(a + b + c);
            }
            scanner.close();
            return sol;
        }

        public void toggleAdj(String[][] sol, int row, int col) {
            if (row + 1 < sol.length) {
                if (sol[row + 1][col].equals("1")) {
                    sol[row + 1][col] = "0";
                } else {
                    sol[row + 1][col] = "1";
                }
            }

            if (row - 1 >= 0) {
                if (sol[row - 1][col].equals("1")) {
                    sol[row - 1][col] = "0";
                } else {
                    sol[row - 1][col] = "1";
                }
            }

            if (col + 1 < sol[0].length) {
                if (sol[row][col + 1].equals("1")) {
                    sol[row][col + 1] = "0";
                } else {
                    sol[row][col + 1] = "1";
                }
            }

            if (col - 1 >= 0) {
                if (sol[row][col - 1].equals("1")) {
                    sol[row][col - 1] = "0";
                } else {
                    sol[row][col - 1] = "1";
                }
            }
        }

        public String word(){
            Scanner scanner = new Scanner(System.in);
            String w = scanner.nextLine();
            int n = w.length();

            int a = (int)'a';
            int z = (int)'z';

            int count = 0;
            for(int i = 0; i < n; i++){
                int curr = (int)w.charAt(i);
                if(curr >= a && curr <= z)
                    count++;
            }

            if(count >= n - count){
                w = w.toLowerCase();
            } else {
                w = w.toUpperCase();
            }

            //System.out.println(w);
            scanner.close();
            return w;
        }

        public String wordCapitalization(){
            Scanner scanner = new Scanner(System.in);
            String word = scanner.nextLine();
            char[] c = word.toCharArray();
            c[0] = ((word.charAt(0) + "").toUpperCase()).charAt(0);
            String sol = new String(c);
            scanner.close();
            return sol;
        }

        public  String nearlyLuckyNumber(){
            Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();
            String s = n + "";
            int cnt = 0;
            for(int i = 0; i < s.length(); i++){
                char c = s.charAt(i);
                if(c == '4' || c == '7')
                    cnt++;
                if(cnt > 7)
                    return "NO";
            }
            scanner.close();
            return (cnt == 7 || cnt == 4)? "YES" : "NO";
        }

        public int stonesOnTheTable(){
            Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();
            scanner.nextLine();
            String s = scanner.nextLine();
            int sol = removeStones(s);
            scanner.close();
            return sol;
        }

        public int removeStones(String s){
            if(isValidStoneArrangement(s))
                return 0;

            int n = s.length();
            int min = n;
            for(int i = 0; i < n; i++){
                int k = removeStones(removeChar(s,i));
                if(k < min)
                    min = k;
            }

            return min + 1;
        }

        public boolean isValidStoneArrangement(String s){
            for(int i = 0; i < s.length() - 1; i++){
                if(s.charAt(i) == s.charAt(i+1))
                    return false;
            }

            return true;
        }

        public String removeChar(String s, int idx){
            String nw = "";
            int n = s.length();

            for(int i = 0; i < n; i++){
                if(i == idx)
                    continue;
                nw = nw + s.charAt(i);
            }
            return nw;
        }

        public String panoramixPrediction(){
            Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();
            int m = scanner.nextInt();
            if(!isPrime(m))
                return "NO";

            for(int i = n + 1; i < m; i++){
                if(isPrime(i))
                    return "NO";
            }

            scanner.close();
            return "YES";
        }

        public boolean isPrime(int n){

            for(int i = 2; i < n; i++){
                float f = (float)n/(float)i;
                int r = (int)f;
                if(f == r)
                    return false;
            }

            return true;
        }

        public String ultraFastMathematician(){
            String sol = "";
            Scanner scanner = new Scanner(System.in);
            String n1 = scanner.nextLine();
            String n2 = scanner.nextLine();
            int n = n1.length();

            for(int i = 0; i < n; i++){
                if(n1.charAt(i) == n2.charAt(i)){
                    sol = sol + "0";
                } else {
                    sol = sol + "1";
                }
            }

            scanner.close();
            return sol;
        }

        public List<Integer> perfectPermutation(){
            Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();

            List<Integer> sol = pPerm(n, new ArrayList<Integer>());

            scanner.close();
            return sol;
        }

        public List<Integer> pPerm(int n, List<Integer> lst){
            List<Integer> sol = new ArrayList<>();
            if(lst.size() == n){
                for(int i = 0; i < lst.size(); i++){
                    if(lst.get(i) == i+1){
                        sol.add(-1);
                        return sol;
                    }
                }

                return lst;
            }

            List<Integer> res;
            for(int i = 0; i < n; i++){
                if(lst.contains(i+1))
                    continue;
                
                lst.add(i+1);

                res = pPerm(n, lst);
                if(res.get(0) != -1 ){
                    return res;
                }
                    
                lst.remove(lst.size()-1);
            }

            sol.add(-1);
            return sol;
        }

        public int arrivalOfTheGeneral(){
            Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();

            List<Integer> line = new ArrayList<>();

            int a = scanner.nextInt();
            int b = scanner.nextInt();       
            line.add(a);
            line.add(b);

            int min;
            int minidx;
            int max;
            int maxidx;
            
            if(a < b){
                min = a;
                minidx = 0;
                max = b;
                maxidx = 1;
            } else {
                min = b;
                minidx = 1;
                max = a;
                maxidx = 0;
            }

            for(int i = 2; i < n; i++){
                int num = scanner.nextInt(); 
                line.add(num);

                if(num > max){
                    max = num;
                    maxidx = i;
                } else if (num <= min){
                    min = num;
                    minidx = i;
                }
            }

            int leftSwap = n-1 - minidx;
            int rightSwap = maxidx;

            scanner.close();
            int sol = leftSwap + rightSwap;

            return (minidx < maxidx )? sol-1: sol;
        }
        
        public float drinks(){
            Scanner scanner = new Scanner(System.in);
            
            int n = scanner.nextInt();
            int num = 0;
            int denom = 0;

            for(int i = 0; i < n; i++){
                num += scanner.nextInt();
                denom += 100;
            }

            scanner.close();
            return (float)num/(float)denom * 100;
        }
    }

        public static void main(String[] args) {
            /*
             * File file = new
             * File("C:\\Users\\Rich\\workspace\\InterviewPractice\\src\\input.txt"); try {
             * BufferedReader br = new BufferedReader(new FileReader(file)); List<String>
             * fileArgs = new ArrayList<>(); String st; while ((st = br.readLine()) != null)
             * fileArgs.add(st);
             * 
             * br.close(); Solution sol = new Solution();
             * //System.out.println(sol.YoungPhysicist(fileArgs));
             * System.out.println(sol.BeautifulMatrix(fileArgs)); } catch (Exception ex) {
             * System.out.println("Exception encountered" + ex.toString()); }
             */
            Solution sol = new Solution();
            // System.out.println(sol.BeautifulMatrix());
            // System.out.println(sol.YoungPhysicist());
            // System.out.println(sol.QueueAtTheSchool());
            // System.out.println(sol.Borze());
            // System.out.println(sol.BeautifulYear());
            // System.out.println(sol.lightsOut());
            //System.out.println(sol.wordCapitalization());
            //System.out.println(sol.nearlyLuckyNumber());
            //System.out.println(sol.stonesOnTheTable());
            //System.out.println(sol.panoramixPrediction());
            //System.out.println(sol.ultraFastMathematician());
            //System.out.println(sol.perfectPermutation());
            //System.out.println(sol.arrivalOfTheGeneral());
            System.out.println(sol.drinks());
        }
    }