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open System

type KusoBuilder() =
    member __.Bind(x, f) = f x
    member __.Return(x) = x
    member __.ReturnFrom(x) = x
    member __.Using(x: #IDisposable, f) = try f x finally if x |> box |> isNull |> not then x.Dispose()
    member __.Zero() = ()
    member __.Combine(_, f) = f()
    member __.TryWith(f, g) = try f() with e -> g e

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let totient n =
    let rec totient isFirst (r, n) d =
        match n % d with
        | 0 -> totient false (r * (d - (if isFirst then 1 else 0)), n / d) d
        | _ -> r, n
    let nearlyPrimes = seq { yield 2; for i in 3 .. 2 .. n do yield i }
    ((1, n), nearlyPrimes) ||> Seq.fold (totient true) |> fst

let totientTest() =
    let expected = [1; 1; 2; 2; 4; 2; 6; 4; 6; 4]

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(*
twiplaの参加者一覧のTSVファイルを作成します。

使用方法
twiplaの印刷用ページを表示してページ全体をクリップボードにコピーし、その内容を文字列にしてtwiplaToTsvの引数に渡します。
*)

open System

let twiplaToTsv (content : string) =

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let factorialNumberSystem n =
    let n = n - 1

    let factorials =
        if n = 0 then [1]
        else
            Seq.initInfinite ((+) 2) |> Seq.scan (*) 1 |> Seq.takeWhile ((>=) n)
            |> Seq.toList |> List.rev

    let factoradic k =

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let r = System.Random()
let expected = [|0; 0; 0; 0; 1|]

let kiyoshi() =
    Seq.initInfinite (fun _ -> r.Next 2) |> Seq.windowed 5
    |> Seq.takeWhile ((<>) expected)
    |> Seq.map Array.head
    |> Seq.append <| expected
    |> Seq.iter (Array.get [|"ズン"; "ドコ"|] >> printf "%s")
    printfn "キ・ヨ・シ！"

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// 単位の定義
[<Measure>] type m
[<Measure>] type s
[<Measure>] type kg
[<Measure>] type 歳

// 単位の別名
[<Measure>] type meter = m
// 組立単位は単位を組み合わせて定義します。単位 N は kg * m / (s * s) の別名扱いです。
[<Measure>] type N = kg * m / (s * s)

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let lazy1 = lazy (printfn "hoge"; 1)
// val lazy1 : Lazy<int> = 値は作成されていません。

// The Force Awakens
lazy1.Force()
// hoge
// val it : int = 1

lazy1.Force()
// val it : int = 1

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open FSharp.Control.Reactive
open FSharp.Control.Reactive.Observable
open System

module FizzBuzzBase =
    /// 100ミリ秒ごとに1, 2, 3, ...を発行
    let numberObservable =
        TimeSpan.FromMilliseconds 100.0 |> interval |> map ((+) 1L)
        |> publish

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/// 素朴なフィボナッチ数列の実装
let rec fib = function
    | 0 -> 0
    | 1 -> 1
    | n -> fib (n - 1) + fib (n - 2)

/// 素朴なフィボナッチ数列の実装(メモ化)
let fibMemo =
    let memo = System.Collections.Generic.Dictionary(dict [0, 0; 1, 1])
    let rec fib n =

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type Word = TrueZoi of string | FalseZoi | TrueOtherwise of string
let isTrue = function TrueZoi _ | TrueOtherwise _ -> true | FalseZoi -> false
let toString = function TrueZoi x | TrueOtherwise x -> x | FalseZoi -> "ぞい"
let countZoi = function TrueZoi _ | FalseZoi -> 1 | TrueOtherwise _ -> 0

let dic =
    [
        [|TrueOtherwise "今日"; FalseZoi|]
        [|TrueOtherwise "も"|]
        [|TrueOtherwise "1"; FalseZoi|]