open System
open System.Runtime.InteropServices


type prostytutka = {imie:string; wiek:int}
let prost1 = {imie="Roksana"; wiek=21}

let rec suma (fl_list:list<float>) =
    match fl_list with
    | head :: tail ->  head + suma tail
    | [] -> 0.0

let lista = [1.1; 1.2; 1.3]

let str = "XXX"

let rec zliczanie_znakow(st:string, ch:char, i:int, n:int) =
 match i with
 | 0 -> if st.[0] = ch then n+1 else n
 | _ -> if st.[0] = ch then zliczanie_znakow(st, ch, i-1, n+1) else zliczanie_znakow(st, ch, i-1, n);


let rec licz (str:string, znak:char) =
   match str.Length with
   | 0 -> 0
   | _ -> if(str.[0] = znak)  then licz(str.[1..], znak) + 1  else licz(str.[1..], znak );


let listaa = [1.1;2.2;3.3;1.0]
let rec sumlist(lista:float list) =
    match lista.Length with
    | 0 -> 0.0
    | _ -> sumlist(lista.[1..]) + lista.[0]


let rec silnia(n) =
    match n with
    |0 |1 -> 1
    |_ -> silnia(n-1) * n


let rec potega(k, n) =
    match n with
    | 0.0 -> 1.0
    | _ -> if n > 0.0 then potega(k, n-1.0) * k
           else 1.0/potega(k, -n)

let rec wdol(n) =
    match n with
    | 0 -> []
    | _ -> n::wdol(n-1)


let  calkowite :int list= [1;2;3;4]

let rec sumator(lista : int list)  =
    match lista.Length with
    | 0 -> 0
    | _ -> if ((lista.[0] % 2) = 0)
            then sumator(lista.[1..]) + lista.[0]
            else sumator(lista.[1..])


let rec sum4(lista:float list) =
    match lista with
    | head::head2::head3::head4::tail -> (head+head2+head3+head4)::sum4(tail)
    | head::head2::head3::tail -> (head+head2+head3)::sum4(tail)
    | head::head2::tail -> head::sum4(tail)
    | head::tail -> head::sum4(tail)
    | [] -> []

let rec sum_head(lista) =
    match lista with
    | head :: tail -> sum_head(tail) + head
    | _ -> 0

let rec zlicz_znak_own(str:string, ch:char) =
    match str.Length with
    | 0 -> 0
    | _ -> if (str.[0] = ch) then 1 +  zlicz_znak_own(str.[1..], ch)  else zlicz_znak_own(str.[1..], ch)

let rec sumator_own(lista:float list) =
    match lista.Length with
    | 0 -> 0.0
    | _ -> lista.[0] + sumator_own(lista.[1..] )


let rec checkElementIfInList(f:float, lista2:float list) =
    match lista2.Length with
    | 0 -> false
    | _ -> if (lista2.[0] = f) then true
            else checkElementIfInList(f, lista2.[1..])

let rec intersec(lista1:float list,lista2:float list) =
    match lista1.Length with
    | 0 -> []
    | _ -> if (checkElementIfInList(lista1.[0],lista2)) then lista1.[0]::intersec(lista1.[1..],lista2)
             else intersec(lista1.[1..],lista2)

[<EntryPoint>]
let main argv =
    printfn "Suma %A" (suma(lista))
    printfn "Zliczone iksy %A" (zliczanie_znakow(str, 'X' ,str.Length-1, 0))
    printfn "Dane kurwy %A" (prost1)
    printfn "Liczałka %A" (licz(str, 'X'))
    printfn "Lista sumator %A" (sumlist(listaa))
    (silnia(4)) |> printfn "Slnia  z 4: %A"
    (potega(2.0, -3.0)) |> printfn "potega  2 do 3: %A"
    (wdol(8)) |> printfn "odlicanie w dol: %A"
    printfn "Suma parzystych %A"   (sumator(calkowite))
    printfn "add3 %A"   (sum4(listaa))
    printfn "sum by head::tail %A"   (sum_head(calkowite))
    printfn "zlicza znak own =  %A"   (zlicz_znak_own("TwojaSara", 'a'))
    printfn "sumator  own =  %A"   (sumator_own([1.1;2.2;3.3]))
    let lista1 = [1.0;2.0;3.0;4.0;5.0]
    let lista2 = [1.0;0.0;0.0;0.0;0.0;5.0;0.0;0.0;0.0;0.0;3.0]
    let inter = intersec(lista1,lista2)
    printfn "wpolne som 1 i 5 i 3  =  %A"  inter


    ignore(Console.ReadKey(true))
    0 // return an integer exit code