using System;

public class Program

{

    public static void Main()

    {

        int[] arr = {2, 4, 6, 9, 11, 14, 20, 36, 48};

        int target = 11;

        Console.WriteLine(linearSearch(arr, target));

    }

    static int linearSearch(int[] arr, int target){

        int start = 0;

        int end = arr.Length - 1;

        int mid = 0;

        while(start <= end) {       

            mid = (start + end ) / 2;

            if(arr[mid] == target)

                return mid;

            if(mid < target)

                start = mid + 1;

            else 

                end = mid - 1;

        }       

        return -1;

    }

}