#light
open System
open System.Linq
open System.IO
open Microsoft.FSharp.Linq

let allowedChars = [|'a'; 'b'; 'o'; 'n'; 'i'; 'm'; 't'|]
let dictionaryPath = "C:\\slowa.txt"

let is_allowed_word word (allowedChars : char[]) =
    word |> Array.forall (fun letter -> allowedChars.Contains(letter))

let findFunc = File.ReadAllLines(dictionaryPath)
                |> Array.filter (fun word -> is_allowed_word (word.ToArray()) allowedChars)
                |> Array.sortByDescending (fun w -> w.Length)

let findFuncCSharpLike = File.ReadAllLines(dictionaryPath)
                        .Where(fun word -> (word.All(fun letter -> allowedChars.Contains(letter))))
                        .OrderByDescending(fun w -> w.Length)
[<EntryPoint>]
let main argv =
    findFunc |> Seq.iter(fun w-> printfn "%s" w)
    System.Console.ReadKey() |> ignore
    0