Day nine

day-09-haskell/.gitignore

@@ -0,0 +1,2 @@
+.stack-work/
+*~

day-09-haskell/Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

day-09-haskell/app/Main.hs

@@ -0,0 +1,19 @@
+module Main (main) where
+
+import System.Environment.Blank ( getArgs )
+import Task1 (task1)
+import Task2 (task2)
+
+main :: IO ()
+main = do
+  args <- getArgs
+  case args of
+    ["1", file] -> do
+      input <- readFile file
+      result <- task1 input
+      print result
+    ["2", file] -> do
+      input <- readFile file
+      result <- task2 input
+      print result
+    _ -> error "Usage: <1|2> <input file>"

day-09-haskell/day09-haskell.cabal

@@ -0,0 +1,54 @@
+cabal-version: 2.2
+
+-- This file has been generated from package.yaml by hpack version 0.37.0.
+--
+-- see: https://github.com/sol/hpack
+
+name:           day09-haskell
+version:        0.1.0.0
+homepage:       https://github.com/githubuser/day09-haskell#readme
+bug-reports:    https://github.com/githubuser/day09-haskell/issues
+author:         Author name here
+maintainer:     example@example.com
+copyright:      2024 Author name here
+license:        BSD-3-Clause
+license-file:   LICENSE
+build-type:     Simple
+
+source-repository head
+  type: git
+  location: https://github.com/githubuser/day09-haskell
+
+library
+  exposed-modules:
+      Common
+      Task1
+      Task2
+  hs-source-dirs:
+      src
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints
+  build-depends:
+      base >=4.7 && <5
+    , flow
+  default-language: Haskell2010
+
+executable day09-haskell-exe
+  main-is: Main.hs
+  hs-source-dirs:
+      app
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , day09-haskell
+  default-language: Haskell2010
+
+test-suite day09-haskell-test
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  hs-source-dirs:
+      test
+  ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , day09-haskell
+  default-language: Haskell2010

day-09-haskell/package.yaml

@@ -0,0 +1,48 @@
+name:                day09-haskell
+version:             0.1.0.0
+github:              "githubuser/day09-haskell"
+license:             BSD-3-Clause
+author:              "Author name here"
+maintainer:          "example@example.com"
+copyright:           "2024 Author name here"
+spec-version:        0.36.0
+
+dependencies:
+- base >= 4.7 && < 5
+
+ghc-options:
+- -Wall
+- -Wcompat
+- -Widentities
+- -Wincomplete-record-updates
+- -Wincomplete-uni-patterns
+- -Wmissing-home-modules
+- -Wpartial-fields
+- -Wredundant-constraints
+
+library:
+  source-dirs: src
+  dependencies:
+  - flow
+
+executables:
+  day09-haskell-exe:
+    main:                Main.hs
+    source-dirs:         app
+    ghc-options:
+    - -threaded
+    - -rtsopts
+    - -with-rtsopts=-N
+    dependencies:
+    - day09-haskell
+
+tests:
+  day09-haskell-test:
+    main:                Spec.hs
+    source-dirs:         test
+    ghc-options:
+    - -threaded
+    - -rtsopts
+    - -with-rtsopts=-N
+    dependencies:
+    - day09-haskell

day-09-haskell/src/Common.hs

@@ -0,0 +1,31 @@
+module Common where
+
+data BlockType = Empty | Allocated Int
+
+instance Show BlockType where
+  show Empty = "(empty)"
+  show (Allocated blockId) = show blockId
+instance Eq BlockType where
+  (==) Empty Empty = True
+  (==) (Allocated a) (Allocated b) = True
+  (==) _ _ = False
+
+type Block = (BlockType, Int)
+length :: Block -> Int
+length (_, l) = l
+
+parseBlocks :: String -> [Block]
+parseBlocks = startWithBlock 0
+  where
+    startWithBlock :: Int -> String -> [Block]
+    startWithBlock _ [] = []
+    startWithBlock blockId (size:rest)
+      | size >= '0' && size <= '9' = (Allocated blockId, read [size]) : startWithEmpty (blockId + 1) rest
+      | otherwise = startWithBlock blockId rest
+
+    startWithEmpty :: Int -> String -> [Block]
+    startWithEmpty _ [] = []
+    startWithEmpty blockId (size:rest)
+      | size >= '0' && size <= '9' = (Empty, read [size]) : startWithBlock blockId rest
+      | otherwise = startWithEmpty blockId rest
+

day-09-haskell/src/Task1.hs

@@ -0,0 +1,42 @@
+module Task1 (task1) where
+
+import Common
+import Control.Monad (join)
+import Flow
+
+type AllocatedBlock = (Int, Int)
+
+task1 :: String -> IO Int
+task1 input = let blocks = parseBlocks input
+                  compacted = compact blocks
+              in do
+                -- print blocks
+                -- print compacted
+                -- print $ showBlocks compacted
+                return $ reduce 0 compacted
+  where
+    compact :: [Block] -> [AllocatedBlock]
+    compact blocks = compactInner blocks (reverse blocks) (minBound :: Int)
+      where
+        compactInner :: [Block] -> [Block] -> Int -> [AllocatedBlock]
+        compactInner [] _ _ = []
+        compactInner _ [] _ = error "Backwards list cannot be empty when forwards list isn't"
+        compactInner forwards ((Empty, _):backwards) curBId = compactInner forwards backwards curBId
+        compactInner forwards ((Allocated _, 0):backwards) curBId = compactInner forwards backwards curBId
+        compactInner ((Empty, 0):forwards) backwards curBId = compactInner forwards backwards curBId
+        compactInner ((Empty, fLength):forwards) ((Allocated bId, bLength):backwards) _
+          | bLength <= fLength = (bId, bLength) : compactInner ((Empty, fLength - bLength) : forwards) backwards bId
+          | otherwise = (bId, fLength) : compactInner forwards ((Allocated bId, bLength - fLength):backwards) bId
+        compactInner ((Allocated fId, fLength):forwards) bAll@((Allocated bId, bLength):_) curBId
+          | fId >= bId = [(bId, bLength)]
+          | otherwise = (fId, fLength) : compactInner forwards bAll curBId
+
+    reduce :: Int -> [AllocatedBlock] -> Int
+    reduce _ [] = 0
+    reduce i ((_, 0): blocks) = reduce i blocks
+    reduce i ((bId, bSize):blocks) = i * bId + reduce (i + 1) ((bId, bSize - 1):blocks)
+
+    showBlocks :: [AllocatedBlock] -> String
+    showBlocks [] = ""
+    showBlocks ((blockId, blockLength):blocks) = (show blockId |> repeat |> take blockLength |> join) ++ showBlocks blocks
+

day-09-haskell/src/Task2.hs

@@ -0,0 +1,48 @@
+module Task2 (task2) where
+
+import Common
+import Flow
+
+task2 :: String -> IO Int
+task2 input = let blocks = parseBlocks input
+                  compacted = compact blocks
+              in do
+                -- print blocks
+                --print compacted
+                return $ reduce 0 compacted
+  where
+    compact :: [Block] -> [Block]
+    compact inputBlocks = compactInner (reverse inputBlocks) inputBlocks
+      where
+        compactInner :: [Block] -> [Block] -> [Block]
+        compactInner [] blocks = blocks
+        compactInner _ [] = error ""
+        compactInner ((Empty, _):inserts) disk = compactInner inserts disk
+        compactInner ((Allocated aId, aLength):inserts) disk = moveFront disk |> compactInner inserts
+          where
+            moveFront :: [Block] -> [Block]
+            moveFront [] = []
+            moveFront (block@(Allocated tId, _):blocks)
+              | tId == aId = block : blocks
+              | otherwise = block : moveFront blocks
+            moveFront (block@(Empty, eLength):blocks)
+              | aLength <= eLength = (Allocated aId, aLength) : (Empty, eLength - aLength) : (combineEmpties $ removeSelf blocks)
+              | otherwise = block : moveFront blocks
+
+            combineEmpties :: [Block] -> [Block]
+            combineEmpties ((Empty, aLen):(Empty, bLen):blocks) = combineEmpties ((Empty, aLen + bLen):blocks)
+            combineEmpties value = value
+
+            removeSelf :: [Block] -> [Block]
+            removeSelf [] = []
+            removeSelf (t@(Allocated tId, tLength):blocks)
+              | tId == aId = (Empty, tLength) : blocks
+              | otherwise = t : removeSelf blocks
+            removeSelf (t:blocks) = t : removeSelf blocks
+
+    reduce :: Int -> [Block] -> Int
+    reduce _ [] = 0
+    reduce i ((_, 0):blocks) = reduce i blocks
+    reduce i ((Empty, eLength):blocks) = reduce (i + 1) ((Empty, eLength - 1):blocks)
+    reduce i ((Allocated bId, bSize):blocks) = i * bId + reduce (i + 1) ((Allocated bId, bSize - 1):blocks)
+

day-09-haskell/stack.yaml

@@ -0,0 +1,67 @@
+# This file was automatically generated by 'stack init'
+#
+# Some commonly used options have been documented as comments in this file.
+# For advanced use and comprehensive documentation of the format, please see:
+# https://docs.haskellstack.org/en/stable/yaml_configuration/
+
+# A 'specific' Stackage snapshot or a compiler version.
+# A snapshot resolver dictates the compiler version and the set of packages
+# to be used for project dependencies. For example:
+#
+# snapshot: lts-22.28
+# snapshot: nightly-2024-07-05
+# snapshot: ghc-9.6.6
+#
+# The location of a snapshot can be provided as a file or url. Stack assumes
+# a snapshot provided as a file might change, whereas a url resource does not.
+#
+# snapshot: ./custom-snapshot.yaml
+# snapshot: https://example.com/snapshots/2024-01-01.yaml
+snapshot:
+  url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/23/0.yaml
+
+# User packages to be built.
+# Various formats can be used as shown in the example below.
+#
+# packages:
+# - some-directory
+# - https://example.com/foo/bar/baz-0.0.2.tar.gz
+#   subdirs:
+#   - auto-update
+#   - wai
+packages:
+- .
+# Dependency packages to be pulled from upstream that are not in the snapshot.
+# These entries can reference officially published versions as well as
+# forks / in-progress versions pinned to a git hash. For example:
+#
+# extra-deps:
+# - acme-missiles-0.3
+# - git: https://github.com/commercialhaskell/stack.git
+#   commit: e7b331f14bcffb8367cd58fbfc8b40ec7642100a
+#
+# extra-deps: []
+
+# Override default flag values for project packages and extra-deps
+# flags: {}
+
+# Extra package databases containing global packages
+# extra-package-dbs: []
+
+# Control whether we use the GHC we find on the path
+# system-ghc: true
+#
+# Require a specific version of Stack, using version ranges
+# require-stack-version: -any # Default
+# require-stack-version: ">=3.1"
+#
+# Override the architecture used by Stack, especially useful on Windows
+# arch: i386
+# arch: x86_64
+#
+# Extra directories used by Stack for building
+# extra-include-dirs: [/path/to/dir]
+# extra-lib-dirs: [/path/to/dir]
+#
+# Allow a newer minor version of GHC than the snapshot specifies
+# compiler-check: newer-minor

day-09-haskell/stack.yaml.lock

@@ -0,0 +1,13 @@
+# This file was autogenerated by Stack.
+# You should not edit this file by hand.
+# For more information, please see the documentation at:
+#   https://docs.haskellstack.org/en/stable/lock_files
+
+packages: []
+snapshots:
+- completed:
+    sha256: 9444fadfa30b67a93080254d53872478c087592ad64443e47c546cdcd13149ae
+    size: 678857
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/23/0.yaml
+  original:
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/23/0.yaml

day-09-haskell/test/Spec.hs

@@ -0,0 +1,2 @@
+main :: IO ()
+main = putStrLn "Test suite not yet implemented"