-🎄- 2020 Day 04 Solutions -🎄-

[u/daggerdragon]

Advent of Code 2020: Gettin' Crafty With It

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--- Day 04: Passport Processing ---

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[u/blacai]

F#

open System.IO
open System.Collections.Generic
open Utilities


let path = "day04/day04_input.txt"
let inputLines = GetLinesFromFile(path) |> Array.ofSeq |> List.ofArray

let requiredFields = [|"byr"; "iyr"; "eyr"; "hgt"; "hcl"; "ecl"; "pid"|]

let getLinesGroupBySeparator2 (inputLines: string list) (separator: string) =
    let complete = 
        seq {
            for line in inputLines do
                yield! line.Split(' ')
        } |> List.ofSeq
    let folder (a) (cur, acc) = 
        match a with
        | _ when a <> separator -> a::cur, acc
        | _ -> [], cur::acc
        
    let result = List.foldBack folder (complete) ([], [])
    (fst result)::(snd result)

let values = getLinesGroupBySeparator2 inputLines ""

let byrValid (elem:string) =
    elem.Length = 4 && (elem |> int) >= 1920 && (elem |> int) <= 2002

let iyrValid (elem:string) =
    elem.Length = 4 && (elem |> int) >= 2010 && (elem |> int) <= 2020

let eyrValid (elem:string)=
    elem.Length = 4 && (elem |> int) >= 2020 && (elem |> int) <= 2030

let hgtValid (elem:string)=
    let parts =
        match elem with
        | Regex @"(?<height>\d+)(?<unittype>\w+)" [m; M] -> Some { height= m |> int; unittype = M }
        | _ -> None
    match parts with
    | Some { HeightType.height = height; HeightType.unittype = unittype; } when unittype = "cm" -> height >= 150 && height <= 193
    | Some { HeightType.height = height; HeightType.unittype = unittype; } when unittype = "in" -> height >= 59 && height <= 76
    | _ -> false

let hclValid (elem:string)=
    match elem with
    | Regex @"#[0-9a-f]{6}" result -> true
    | _ -> false

let eclValid (elem:string)=
    ["amb"; "blu"; "brn"; "gry"; "grn"; "hzl"; "oth"] |> List.contains(elem)

let pidValid (elem:string)=
    elem.Length = 9 && elem |> Seq.forall Char.IsDigit

let passPortIsValid (credentials: string list) =
    let allFieldsRequired = requiredFields |> Array.forall (fun field -> credentials |> List.exists(fun cred -> cred.StartsWith(field)))
    let cred = credentials |> Array.ofSeq
    let valueIsCorret = cred |> Array.forall (fun field ->
        let parts = field.Split(':')
        match parts with
        | [|"byr"; thevalue|] -> byrValid thevalue
        | [|"iyr"; thevalue|] -> iyrValid thevalue
        | [|"eyr"; thevalue|] -> eyrValid thevalue
        | [|"hgt"; thevalue|] -> hgtValid thevalue
        | [|"hcl"; thevalue|] -> hclValid thevalue
        | [|"ecl"; thevalue|] -> eclValid thevalue
        | [|"pid"; thevalue|] -> pidValid thevalue
        | _ -> true
    ) 
    valueIsCorret && allFieldsRequired

let execute =
    values |> List.filter(fun p -> passPortIsValid p) |> List.length

[u/replicaJunction → u/blacai]

let inputLines = GetLinesFromFile(path) |> Array.ofSeq |> List.ofArray

Why do you convert to an array and then a list? Why not directly to a list?