Advent of Code 2023 1-2

advent2023-1-2.fs

let realFirstDigitRegex = Regex("one|two|three|four|five|six|seven|eight|nine|[0-9]")
let realLastDigitRegex = Regex("one|two|three|four|five|six|seven|eight|nine|[0-9]", RegexOptions.RightToLeft)

let matchToInt = function
    | "one"   -> 1
    | "two"   -> 2
    | "three" -> 3
    | "four"  -> 4
    | "five"  -> 5
    | "six"   -> 6
    | "seven" -> 7
    | "eight" -> 8
    | "nine"  -> 9
    | x       -> int x

let realSumOfCalibrationValues =
    Seq.fold (fun acc (line: string) ->
       let first = realFirstDigitRegex.Match(line).Value |> matchToInt
       let last = realLastDigitRegex.Match(line).Value |> matchToInt
       acc + 10*first + last
    ) 0

["three1abc2"
 "pqr3stu8vfourwx"
 "a1b2c3d4e5f"
 "treb7uche0t" ]
|> realSumOfCalibrationValues
|> System.Console.WriteLine // 151