// 140115 uppgift 3
let rec add arr =
    let len = Array.length arr
    if len = 1 then
        arr.[0]
    else
        add arr.[0..len/2-1] + add arr.[len/2..len-1]

printfn "%f" (add [| 5.0;6.0;7.0;8.0 |])

// 140115 uppgift 5
let avg floatList =
    let sum = ref 0.0

    let rec foo (floatList : float list) =
        match floatList with
        | x::xs -> sum := !sum + x; foo xs
        | [] -> ()

    foo floatList
    printfn "%f" (!sum/float(floatList.Length))

avg [2.2; 3.3; 4.4]

// 140115 uppgift 6
type tree<'a> = Node of tree<'a> * 'a * tree<'a> | Empty
let rec getBågar tree =
    match tree with
    | Node(Empty, b, Empty) -> 0
    | Node(Empty, b, c) -> 1 + getBågar c
    | Node(a, b, Empty) -> 1 + getBågar a
    | Node(a, b, c) -> 2 + getBågar a + getBågar c
    | Empty -> 0

printfn "%A" ([ 5.0;6.0;7.0;8.0] @ [1.0;2.0;3.0;4.0])

// 140609 uppgift 1

let rec opt_remove list =
    match list with
    | None::tail -> opt_remove tail
    | Some x::tail -> x::opt_remove tail
    | [] -> []

//let opt_remove_v2 l =
 //   l |> List.filter (fun x -> not (x = None)) |> List.map (fun (Some x) -> x)

printfn "%A" (opt_remove [Some 17; None; None; Some 3; Some 0])

// 140609 uppgift 3
let rec dot arr1 arr2 =
    let len1 = Array.length arr1
    let len2 = Array.length arr2
    if len1 = 0 && len2 = 0 then
        0
    else if len1 = len2 then
        arr1.[0] * arr2.[0] + dot (arr1.[1..]) (arr2.[1..])
    else
        failwith "u suk"

printfn "%A" (dot [|1;2;3;4|] [|5;6;7;9|])

// 140609 uppgift 5
let printlist list =
    printf "[ "
    let rec printlistrec list =
        match list with
        | [] -> ()
        | [x] -> printf "%A" x
        | x::tail -> printf "%A; " x; printlistrec tail
    in printlistrec list
    printf " ]\n"

printlist [1;2;3]

// 140609 uppgift 6
type sphereTree = Sphere of sphereTree * (float * float * float) * float * sphereTree | Empty

let calcVolume radius = (4.0 * 3.14159265358979323846264338327950 * radius * radius * radius) / 3.0

let rec calcTree tree =
    match tree with
    | Empty -> 0.0
    | Sphere(Empty, _, radius, Empty) -> calcVolume radius
    | Sphere(s1, _, radius, Empty) -> (calcTree s1) + (calcVolume radius)
    | Sphere(Empty, _, radius, s2) -> (calcTree s2) + (calcVolume radius)
    | Sphere (s1, _, radius, s2) -> (calcTree s1) + (calcVolume radius) + (calcTree s2)

// 140820 uppgift 1
let remove l1 l2 =
    List.filter (fun x -> not(List.exists (fun y -> x = y) l1)) l2

printfn "%A" (remove [1;2;3;4;5;6] [4;5;6;7;8;9])

System.Console.ReadKey() |> ignore