// Map Function
let mapfunc (k, v) =
    v |> Seq.map (fun(pet) -> (pet, 1))

// Reduce Function
let reducefunc (k, (vs:seq<int>)) =
    let count = vs |> Seq.sum
    k, Seq.ofList([count])

// Map Reduce
let mapreduce map reduce (inputs:seq<_*_>) =
    let intermediates = inputs |> Seq.map map |> Seq.concat
    let groupings = intermediates |> Seq.groupBy fst |> Seq.map (fun(x,y) -> x, Seq.map snd y)
    let results = groupings |> Seq.map reduce
    results

let alice = ("Alice", ["Dog";"Cat"])
let bob = ("Bob",["Cat"])
let charlie = ("Charlie",["Mouse"; "Cat"; "Dog"])
let dennis = ("Dennis", [])

let people = [alice; bob; charlie; dennis]

[<EntryPoint>]
let main argv =
    let results = people |> mapreduce mapfunc reducefunc

    for result in results do
        let animal = fst result
        let count = ((snd result) |> Seq.toArray).[0]
        printfn "%s : %s" animal (count.ToString())

    System.Console.WriteLine("done...")
    System.Console.ReadKey() |> ignore
    0