diff options
Diffstat (limited to 'Day7/app/Main.hs')
| -rw-r--r-- | Day7/app/Main.hs | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/Day7/app/Main.hs b/Day7/app/Main.hs index fa1d522..15bc30a 100644 --- a/Day7/app/Main.hs +++ b/Day7/app/Main.hs @@ -27,7 +27,8 @@ parseDay7Input :: String -> Directory parseDay7Input = buildDirectoryFromCommands . parseCommands parseCommands :: String -> [Command] -parseCommands = map parseCommand . splitAtDollarSign +parseCommands = map parseCommand . skipEmptyLines . splitAtDollarSign + where skipEmptyLines = filter (/= "") -- splitting at all dollar signs can yield empty commands, for instance if the file starts with $. splitAtDollarSign :: String -> [String] splitAtDollarSign [] = [] @@ -80,4 +81,38 @@ parseLsLine fileSizeAndName = Fil $ File nn (read sz) verifyWordCount _ = error "Wrong number of words in ls file entry." solveDay7Parts :: Directory -> (Int, Int) -solveDay7Parts = error "unimplemented"
\ No newline at end of file +solveDay7Parts d = (solveDay7Part1 d, solveDay7Part2 d) + +data DirWithAccumulatedSize = DirWithAccumulatedSize String Int [DirWithAccumulatedSize] +newtype DirWithAcuumulatedSizeFlat = DirWithAcuumulatedSizeFlat (String, Int) + +solveDay7Part1 :: Directory -> Int +solveDay7Part1 = + sum + . map (\(DirWithAcuumulatedSizeFlat (_,s)) -> s) + . filter (\(DirWithAcuumulatedSizeFlat (n,s)) -> s <= 100000) + . flattenDirWithAccumulatedSize + . convertToAccumulatedSizeTree + +convertToAccumulatedSizeTree :: Directory -> DirWithAccumulatedSize +convertToAccumulatedSizeTree (Directory name subdirs files) = + DirWithAccumulatedSize name (sum subdirSizes + sum fileSizes) sizedSubdirs + where sizedSubdirs = map convertToAccumulatedSizeTree subdirs + fileSizes = map (\(File _ size) -> size) files + subdirSizes = map (\(DirWithAccumulatedSize _ size _) -> size) sizedSubdirs + +flattenDirWithAccumulatedSize :: DirWithAccumulatedSize -> [DirWithAcuumulatedSizeFlat] +flattenDirWithAccumulatedSize (DirWithAccumulatedSize name size []) = [DirWithAcuumulatedSizeFlat (name, size)] +flattenDirWithAccumulatedSize (DirWithAccumulatedSize name size (sd:sds)) = flattenDirWithAccumulatedSize sd ++ flattenDirWithAccumulatedSize (DirWithAccumulatedSize name size sds) + +solveDay7Part2 :: Directory -> Int +solveDay7Part2 d = (\(DirWithAcuumulatedSizeFlat (_,s)) -> s) $ smallestDirLargerThan requiredSpace flattenedDirs + where flattenedDirs = flattenDirWithAccumulatedSize accumulatedSizeTree + accumulatedSizeTree = convertToAccumulatedSizeTree d + requiredSpace = rootSize accumulatedSizeTree - (70000000 - 30000000) + rootSize (DirWithAccumulatedSize _ s _) = s + +smallestDirLargerThan :: Int -> [DirWithAcuumulatedSizeFlat] -> DirWithAcuumulatedSizeFlat +smallestDirLargerThan m = foldl1 smallestSize . filter ((m <=) . si) -- too lazy to handle empty list case -> foldl1 + where smallestSize d1 d2 = if si d1 < si d2 then d1 else d2 + si (DirWithAcuumulatedSizeFlat (_,s)) = s
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