using System;

using System.Threading;

public class Program

{

​

    public static void Main()

    {       

        //Problem #3

        // Write a function that will find a hidden number used by "Api" object when "GetResult" executed. "GetResult" takes any number as an input and returns false if input is lower then hidden number or true if equal or greater. You need to find hidden number efficiently.

        // hidden number randomly generated in a range between 1 and 1000

        // Example: 

        // var secret = new Secret(); object will generate a random number and store it. 505 in this example 

        // your code

        // Expected answer is 505

        var api = new Api();        

        Console.WriteLine("Programming Problem - search - Start");

        int min = 1;

        int max = 1000;         

        int result = BinarySearchRecursive(ref api, min, max);

        Console.WriteLine("My answer: " + result);

        int i = 990;

while (i < 1000) 

{

  Console.Write(i);

    api.SetValue(i);

            int res = BinarySearchRecursive(ref api, min, max);

        Console.Write(" My answer: " + res);

    if(api.GetValue()!=res)

    {

        Console.Write(" Doesn't match!");

    }

    Console.WriteLine("");

  i++;

}

        Console.WriteLine("Programming Problem - search - End");

    }       

    public static int BinarySearchRecursive(ref Api api, int min, int max)  

{  

        int myGuess = (min+max)/2;          

        var result = api.GetResult(myGuess);        

        Console.WriteLine("Between " + min + " " + max + ": checking " + myGuess +". Received " + result);

        if(result==true)

        {

            if(min==max)

            {

                return min;

            }           

            return BinarySearchRecursive(ref api, min, myGuess);            

        }

        else

        {

​

            return BinarySearchRecursive(ref api, myGuess+1, max);  

        }

 }  

​

    public class Api

    {

       private  int _secretNumber;

​

       public Api()

       {

           var random = new Random();

           _secretNumber = random.Next(1,1000);

           Console.WriteLine("Secret number is " + _secretNumber.ToString() + ". Find me");

       }

        public int GetValue()

       {

            return _secretNumber;

       }

                public void SetValue(int val)

       {

            _secretNumber =val;

       }

        public bool GetResult(int number)

       {

            //Thread.Sleep(200);

            if(number<_secretNumber)

            {

                return false;

            }

​

            return true;

       }

    }   

}

​