using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("kolko chisla:");

        int puti=int.Parse(Console.ReadLine());

        if(puti<=10)

        {

        int [] arr=new int[puti];

        for(int i=0;i<puti;i++)

        {

            int n=int.Parse(Console.ReadLine());//5

            arr[i]=n;

        }

        Console.WriteLine(String.Join(" ",arr));

​

        Console.WriteLine(arr.Sum());

        Console.WriteLine(arr.Average());

        for(int i=0;i<arr.Length;i++)

        {

            Console.WriteLine("{0}->{1}",arr[i],i);

        }

        for(int i=0;i<arr.Length;i+=2)

        {

            arr[i]=arr[i]*2;

        }

        Console.WriteLine(String.Join(" ",arr));

        }

    }

}