using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

    int BinarySearch(int[] arr, int start, int end, int x)

    {

        if (start > end)

            return -1;

        int mid = (start + end)/2;

        if (arr[mid] == x)

            return mid;

        else if (arr[mid] < x)

            return BinarySearch(arr, mid + 1, end, x);

        else

            return BinarySearch(arr, start, mid - 1, x);

    }

}