using System;

public class Program

{

    public static int SumZugi(int[] arr)

    {

        return SumZugi(arr, 0);

    }

    public static int SumZugi(int[] arr, int i)

    {

        if(i==arr.Length)

            return 0;

        if(arr[i]%2==0)

            return arr[i]+SumZugi(arr,i+1);//1,6,5,4,2

        return SumZugi(arr,i+1);

    }

    public static int PlaceZugi(int[] arr)

    {

        return PlaceZugi(arr,0);

    }

    public static int PlaceZugi(int[] arr,int i)

    {

        if(i==arr.Length)

            return 0;

        if(i%2==0)

            return arr[i]+ PlaceZugi(arr,i+1);

        return PlaceZugi(arr,i+1);

    }

    public static bool Ola(int[] arr)

    {

        return Ola(arr,0);

    }

    public static bool Ola(int[] arr, int i)

    {

        if(i==arr.Length-1)

            return true;

        if(arr[i]>=arr[i+1])

            return false;

        return Ola(arr,i+1);    

    }

    public static bool Palindrom(int[] arr)

    {

        return Palindrom(arr, 0,arr.Length-1);

    }

    public static bool Palindrom(int[]arr, int i, int j)

    {

        if(i>=j)

            return true;

        if(arr[i]!=arr[j])

            return false;

        return Palindrom(arr, i+1, j-1);

    }

    public static void Main()

    {

        int[] arr = new int[5];

        arr[0]=1;

        arr[1]=6;

        arr[2]=5;

        arr[3]=6;

        arr[4]=1;

        Console.WriteLine(Palindrom(arr));

    }

}