A Babel of Languages on CodinGame

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F#

Checking the sample code

(Contributed by Djoums):

open System
open System.Text.RegularExpressions
(* Console.In.ReadLine().ToCharArray() *)
"CG".ToCharArray()
    |> Array.map (fun c -> Convert.ToString(int c, 2).PadLeft(7, '0'))
    |> String.Concat
    |> fun s -> Regex.Matches(s, "(.)\1*")
    |> Seq.map (fun m -> m.ToString())
    |> Seq.map (fun s -> (if s.[0] = '1' then "0 " else "00 ") + (String.replicate s.Length "0"))
    |> String.concat " "
    |> printfn "%s"

Looking at the syntax

This is very different from an imperative style code! A proper introduction to functional programming (FP) is unfortunately beyond the scope of this playground.
|> is the pipe forward operator, used to chain the function calls.
Comments are between (* and *). Don't ask...
There are some function names (Convert.ToString and PadLeft) which look exactly the same as in our C# solution. This is not a coincidence. As C#, F# and VB .NET are all targeting Microsoft's Common Language Infrastructure (CLI) on .NET Core, they share some of the standard libraries.
fun x -> defines anonymous functions on the fly.
if..then..else is not a conditional statement, but a conditional expression so it returns a result.

Other characteristics

F# defines itself as "functional-first" programming language. Unlike Haskell, which is pure, uncompromising FP, with F# you can mix in some imperative or object-oriented style in your code, when it makes sense. However, this can be abused. To demonstrate, I show an F# Chuck Norris solution in imperative style. Don't try this at home! :-)

open System
(* let m = Console.In.ReadLine() *)
let m = "CG"
let c = [| "00"; "0" |]
let mutable b = ""
for ch in m do
    b <- b + Convert.ToString(ch |> int, 2).PadLeft(7, '0')
let mutable a = ""
a <- a + c.[(b.[0] |> int) - ('0' |> int)] + " 0"
for i = 1 to (String.length b) - 1 do
    if b.[i] = b.[i - 1] then
        a <- a + "0"
    else
        a <- a + " " + c.[(b.[i] |> int) - ('0' |> int)] + " 0"
(* eprintfn "Debug message" *)
printfn "%s" a

Resources to check

Meme

Coming next...

The natural choice for the next section is the "most-FP language of all FP languages", Haskell...

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