adventofcode1702/app/advent02.hs

   1 module Main(main) where
   2
   3 import Text.Parsec
   4 import Text.ParserCombinators.Parsec.Number
   5
   6
   7 main :: IO ()
   8 main = do
   9         text <- readFile "data/advent02.txt"
  10         let sheet = successfulParse $ parseFile text
  11         print $ part1 sheet
  12         print $ part2 sheet
  13
  14
  15 part1 :: [[Int]] -> Int
  16 part1 = sum . map p1cSum
  17
  18 part2 :: [[Int]] -> Int
  19 part2 = sum . map p2cSum
  20
  21
  22 p1cSum :: [Int] -> Int
  23 p1cSum row = (maximum row) - (minimum row)
  24
  25 p2cSum :: [Int] -> Int
  26 p2cSum digits = sum [a `div` b | a <- digits, b <- digits, a /= b, a `mod` b == 0]
  27
  28
  29
  30 sFile = sLine `sepEndBy` newline
  31 sLine = int `sepBy` onlySpaces
  32
  33 onlySpaces = many (oneOf " \t")
  34
  35 parseFile :: String -> Either ParseError [[Int]]
  36 parseFile input = parse sFile "(unknown)" input
  37
  38 parseLine :: String -> Either ParseError [Int]
  39 parseLine input = parse sLine "(unknown)" input
  40
  41 successfulParse :: Either ParseError [a] -> [a]
  42 successfulParse (Left _) = []
  43 successfulParse (Right a) = a
  44