2024-02 in haskell
This commit is contained in:
parent
e51c318b87
commit
c4b50467fe
4 changed files with 1108 additions and 0 deletions
6
2024/02-Red-Nosed_Reports/example
Normal file
6
2024/02-Red-Nosed_Reports/example
Normal file
|
@ -0,0 +1,6 @@
|
||||||
|
7 6 4 2 1
|
||||||
|
1 2 7 8 9
|
||||||
|
9 7 6 2 1
|
||||||
|
1 3 2 4 5
|
||||||
|
8 6 4 4 1
|
||||||
|
1 3 6 7 9
|
47
2024/02-Red-Nosed_Reports/first.hs
Normal file
47
2024/02-Red-Nosed_Reports/first.hs
Normal file
|
@ -0,0 +1,47 @@
|
||||||
|
-- requires cabal install --lib megaparsec parser-combinators heap vector
|
||||||
|
module Main (main) where
|
||||||
|
|
||||||
|
import Control.Monad (void, when)
|
||||||
|
import Data.Void (Void)
|
||||||
|
import Text.Megaparsec
|
||||||
|
import Text.Megaparsec.Char
|
||||||
|
|
||||||
|
exampleExpectedOutput = 2
|
||||||
|
|
||||||
|
type Report = [Int]
|
||||||
|
type Input = [Report]
|
||||||
|
|
||||||
|
type Parser = Parsec Void String
|
||||||
|
|
||||||
|
parseNumber :: Parser Int
|
||||||
|
parseNumber = read <$> some digitChar <* optional hspace
|
||||||
|
|
||||||
|
parseReport :: Parser Report
|
||||||
|
parseReport = some parseNumber
|
||||||
|
|
||||||
|
parseInput' :: Parser Input
|
||||||
|
parseInput' = some (parseReport <* eol) <* eof
|
||||||
|
|
||||||
|
parseInput :: String -> IO Input
|
||||||
|
parseInput filename = do
|
||||||
|
input <- readFile filename
|
||||||
|
case runParser parseInput' filename input of
|
||||||
|
Left bundle -> error $ errorBundlePretty bundle
|
||||||
|
Right input' -> return input'
|
||||||
|
|
||||||
|
compute :: Input -> Int
|
||||||
|
compute input = length . filter id $ map (valid . differences) input
|
||||||
|
where
|
||||||
|
differences report = zipWith (-) (init report) (tail report)
|
||||||
|
valid :: Report -> Bool
|
||||||
|
valid rs@(r:_) | r > 0 = all (\v -> v > 0 && v <= 3) rs
|
||||||
|
| r < 0 = all (\v -> v < 0 && v >= (-3)) rs
|
||||||
|
| otherwise = False
|
||||||
|
|
||||||
|
main :: IO ()
|
||||||
|
main = do
|
||||||
|
example <- parseInput "example"
|
||||||
|
let exampleOutput = compute example
|
||||||
|
when (exampleOutput /= exampleExpectedOutput) (error $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
|
||||||
|
input <- parseInput "input"
|
||||||
|
print $ compute input
|
1000
2024/02-Red-Nosed_Reports/input
Normal file
1000
2024/02-Red-Nosed_Reports/input
Normal file
File diff suppressed because it is too large
Load diff
55
2024/02-Red-Nosed_Reports/second.hs
Normal file
55
2024/02-Red-Nosed_Reports/second.hs
Normal file
|
@ -0,0 +1,55 @@
|
||||||
|
-- requires cabal install --lib megaparsec parser-combinators heap vector
|
||||||
|
module Main (main) where
|
||||||
|
|
||||||
|
import Control.Monad (void, when)
|
||||||
|
import qualified Data.List as L
|
||||||
|
import Data.Void (Void)
|
||||||
|
import Text.Megaparsec
|
||||||
|
import Text.Megaparsec.Char
|
||||||
|
|
||||||
|
import Debug.Trace
|
||||||
|
|
||||||
|
exampleExpectedOutput = 4
|
||||||
|
|
||||||
|
type Report = [Int]
|
||||||
|
type Input = [Report]
|
||||||
|
|
||||||
|
type Parser = Parsec Void String
|
||||||
|
|
||||||
|
parseNumber :: Parser Int
|
||||||
|
parseNumber = read <$> some digitChar <* optional hspace
|
||||||
|
|
||||||
|
parseReport :: Parser Report
|
||||||
|
parseReport = some parseNumber
|
||||||
|
|
||||||
|
parseInput' :: Parser Input
|
||||||
|
parseInput' = some (parseReport <* eol) <* eof
|
||||||
|
|
||||||
|
parseInput :: String -> IO Input
|
||||||
|
parseInput filename = do
|
||||||
|
input <- readFile filename
|
||||||
|
case runParser parseInput' filename input of
|
||||||
|
Left bundle -> error $ errorBundlePretty bundle
|
||||||
|
Right input' -> return input'
|
||||||
|
|
||||||
|
compute :: Input -> Int
|
||||||
|
compute input = length . filter id $ map (any (valid . differences) . candidates) input
|
||||||
|
where
|
||||||
|
candidates :: Report -> [Report]
|
||||||
|
candidates report = report : [splitThis i|i<-[1..length report]]
|
||||||
|
where
|
||||||
|
splitThis i = let (l, r) = L.splitAt i report
|
||||||
|
in init l ++ r
|
||||||
|
differences report = zipWith (-) (init report) (tail report)
|
||||||
|
valid :: Report -> Bool
|
||||||
|
valid rs@(r:_) | r > 0 = all (\v -> v > 0 && v <= 3) rs
|
||||||
|
| r < 0 = all (\v -> v < 0 && v >= (-3)) rs
|
||||||
|
| otherwise = False
|
||||||
|
|
||||||
|
main :: IO ()
|
||||||
|
main = do
|
||||||
|
example <- parseInput "example"
|
||||||
|
let exampleOutput = compute example
|
||||||
|
when (exampleOutput /= exampleExpectedOutput) (error $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
|
||||||
|
input <- parseInput "input"
|
||||||
|
print $ compute input
|
Loading…
Add table
Reference in a new issue