using System;

public class Program

{

    public static void Main()

    {

        int i,j,min,index,h=0,temp;

        Console.Write("Enter length of array:");

        int num1=int.Parse(Console.ReadLine());

        int[] array=new int[num1];

        Console.Write("Enter Number:");

        for(i=0;i<num1;i++)

            array[i]=int.Parse(Console.ReadLine());

        for(i=0;i<num1-1;i++)

        {

            index=h;

            min=array[h];

            for(j=h;j<i;j++)

            {

                if(array[j]<min)

                {

                    min=array[j];

                    index=j;

                }

            }

            temp=array[i];

            array[i]=min;

            array[index]=temp;

            h++;    

        }

        Console.Write("Enter a key:");

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

        int first=0,last=num1;

        int middle=(first+last)/2;

        bool blkey=false;

        while(last>=first)

        {

            if(array[middle]==key)

            {

                blkey=true;

                break;

            }

            else if(array[middle]>key)

            {

                last=array[middle]-1;

                middle=(first+last)/2;

            }

            else

            {

                first=array[middle]+1;

                middle=(first+last)/2;

            }

        }

        if(blkey)

            Console.WriteLine("Found");

        else

            Console.WriteLine("Not Found");

    }

}