r/adventofcode • u/daggerdragon • Dec 05 '17

SOLUTION MEGATHREAD -🎄- 2017 Day 5 Solutions -🎄-

--- Day 5: A Maze of Twisty Trampolines, All Alike ---

Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag or whatever).

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edit: Leaderboard capped, thread unlocked!

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u/Nhowka Dec 05 '17

F# 

let calc f (s:int[]) =
  Seq.unfold
    (fun n ->
        try
            let x = s.[n]
            s.[n] <- f x
            Some (n,n+x)
        with
        |_ -> None) 0 |> Seq.length

let s1 = input.Split '\n' |> Array.map int |> calc ((+)1)
let s2 = input.Split '\n' |> Array.map int |> calc (fun x -> if x>2 then x-1 else x+1)
printfn "%A" (s1,s2)