Add 2020 day 04

haskellAoC/src/Y2020/Day04.hs

@@ -0,0 +1,57 @@
+module Y2020.Day04 (y20day04) where
+
+import Data.Char
+import Data.Maybe
+import Data.List.Split
+import qualified Data.Map as M
+
+data RawPassport = RawPassport {
+  birth_year :: String
+  , issue_year :: String
+  , expir_year :: String
+  , height :: String
+  , hair_color :: String
+  , eye_color :: String
+  , passport_id :: String
+  } deriving (Show)
+
+parsePassport :: String -> Maybe RawPassport
+parsePassport input = do
+  byr <- M.lookup "byr" mapped
+  iyr <- M.lookup "iyr" mapped
+  eyr <- M.lookup "eyr" mapped
+  hgt <- M.lookup "hgt" mapped
+  hcl <- M.lookup "hcl" mapped
+  ecl <- M.lookup "ecl" mapped
+  pid <- M.lookup "pid" mapped
+  return (RawPassport byr iyr eyr hgt hcl ecl pid)
+  where mapped = M.fromList $ map (\a -> (a !! 0, a !! 1)) $ map (splitOn ":") $ splitOn " " input
+
+allTrue :: [Bool] -> Bool
+allTrue = all (== True)
+
+checkDigitInRange :: Int -> Int -> String -> Bool
+checkDigitInRange mini maxi input = allTrue $ map ($ input) [(all (isDigit)), ((>= mini) . read), ((<= maxi) . read)]
+
+validatePassport :: RawPassport -> Bool
+validatePassport pass = allTrue [validatePassID, validateBirth, validateIssued, validateExpiration, validateHeight, validateHairColor, validateEyeColor]
+  where validateBirth = checkDigitInRange 1920 2002 $ birth_year pass
+        validateIssued = checkDigitInRange 2010 2020 $ issue_year pass
+        validateExpiration = checkDigitInRange 2020 2030 $ expir_year pass
+        validateHeight = not unitAvailable && (correctHeightCm || correctHeightIn)
+          where correctHeightCm = checkDigitInRange 150 193 $ (splitOn "cm" (height pass)) !! 0
+                correctHeightIn = checkDigitInRange 59 76 $ (splitOn "in" (height pass)) !! 0
+                unitAvailable = all (isDigit) (height pass)
+        validateHairColor = allTrue $ map ($ hair_color pass) [((== '#') . head), (all (`elem` "0123456789abcdef") . tail), ((== 7) . length)]
+        validateEyeColor = (eye_color pass) `elem` ["amb", "blu", "brn", "gry", "grn", "hzl", "oth"]
+        validatePassID = allTrue $ map ($ passport_id pass) [((== 9) . length), (all (isDigit))]
+
+y20day04 :: [String] -> (String, String)
+y20day04 input = (part1, part2)
+  where part1 = show $ length $ passports
+        part2 = show $ length $ validPassports
+        passports = concatMap maybeToList $ map parsePassport $ map replaceNL $ splitOn "\n\n" $ unlines input
+        replaceNL = map repl
+        repl '\n' = ' '
+        repl c = c
+        validPassports = filter validatePassport passports

haskellAoC/src/Y2020/Days.hs

@@ -3,9 +3,11 @@ module Y2020.Days (year2020) where
 import Y2020.Day01
 import Y2020.Day02
 import Y2020.Day03
+import Y2020.Day04
 
 
 year2020 :: String -> [String] -> (String, String)
 year2020 "01" = y20day01
 year2020 "02" = y20day02
 year2020 "03" = y20day03
+year2020 "04" = y20day04