open System
open Microsoft.FSharp.Linq
open System.Linq

let GetRandomNumbers count =
    let rnd = System.Random()
    List.init count (fun _ -> (rnd.Next() % 100))

let rec BinarySearch (arr: Collections.Generic.List<int>, low:int, high:int, value:int) =
    if (high < low) then
        box None;
    else
        Console.WriteLine("Qual o proximo elemento a ser testado?");
        let midGuess = Console.ReadLine();
        let midGuessInt = Convert.ToInt32(midGuess);
        let mid = (low + high) / 2

        if (mid <> midGuessInt) then
            printf "Resposta correta %d" mid
            Console.WriteLine();
            null
        else
            if (arr.[mid] > value) then
                    BinarySearch (arr, low, mid-1, value)
                else if (arr.[mid] < value) then
                    BinarySearch (arr, mid+1, high, value)
                else
                    match box arr.[mid] with
                        | null -> box None
                        | x -> box(Some(x))


let PrintIndexes (high: int) =
    for i = 0 to high do
        printf "%d   " i

let PrintList(list: Collections.Generic.List<int>) =
    for i = 0 to list.Count - 1 do
        printf "%d  " (list.ElementAt(i))

[<EntryPoint>]
let main argv =
    let list = GetRandomNumbers(10);
    let list = list.OrderBy((fun x -> x)).ToList();

    PrintIndexes (list.Count - 1)
    Console.WriteLine();

    PrintList list;
    Console.WriteLine();

    let random = new Random();
    let value = random.Next(0, list.Count - 1);

    printf "Indique quais sao elementos testados para a pesquisa do elemento %d" (list.ElementAt(value))
    Console.WriteLine();

    let result = BinarySearch(list, 0, list.Count - 1, list.ElementAt(value))

    if result <> null then
        Console.WriteLine("Voce acertou");
    else
        Console.WriteLine("Voce errou");

    Console.WriteLine(result)
    Console.WriteLine("Press any key to continue...");
    Console.ReadLine() |> ignore
    0 // return an integer exit code