2015 day 1 part 1

Author: teivah

2015/day3-haskell/Main.hs

@@ -5,20 +5,20 @@ main :: IO ()
 main = do
   content <- readFile "input.txt"
   let map = Map.empty
-  let res = fn1 content map 0 0
+  let res = fn1 content map (0, 0)
   print res
-  let res = fn2 content map 0 0 0 0 True
+  let res = fn2 content map (0, 0) (0, 0) True
   print res
 
-fn1 [] map _ _ = Map.size map
-fn1 (x:xs) map row col = fn1 xs map2 row2 col2
+fn1 [] map (_, _) = Map.size map
+fn1 (x:xs) map (row, col) = fn1 xs map2 (row2, col2)
   where
     map2 = Map.insert (row, col) True map
     (row2, col2) = transform x row col
 
-fn2 [] map _ _ _ _ _ = Map.size map
-fn2 (x:xs) map sRow sCol rRow rCol sTurn =
-  fn2 xs map2 sRow2 sCol2 rRow2 rCol2 sTurn2
+fn2 [] map (_, _) (_, _) _ = Map.size map
+fn2 (x:xs) map (sRow, sCol) (rRow, rCol) sTurn =
+  fn2 xs map2 (sRow2, sCol2) (rRow2, rCol2) sTurn2
   where
     map2 =
       if sTurn

2016/day1-haskell/Justfile

@@ -0,0 +1,2 @@
+build:
+  ghcid --command="stack ghci Main.hs" --test=":main"

2016/day1-haskell/Main.hs

@@ -0,0 +1,48 @@
+import Data.List.Split (splitOn)
+import System.IO
+
+data Direction
+  = North
+  | South
+  | East
+  | West
+
+main :: IO ()
+main = do
+  content <- readFile "input.txt"
+  let s = splitOn ", " content
+  let res = fn1 s North 0 0
+  print res
+
+fn1 :: [String] -> Direction -> Int -> Int -> Int
+fn1 [] _ row col = abs row + abs col
+fn1 (x:xs) dir row col = do
+  let (to, count) = parse x
+  let dir2 = turn dir to
+  let (row2, col2) = move dir2 count row col
+  fn1 xs dir2 row2 col2
+
+parse :: String -> (Char, Int)
+parse s = (head s, read (drop 1 s) :: Int)
+
+turn North turn =
+  case turn of
+    'R' -> East
+    'L' -> West
+turn West turn =
+  case turn of
+    'R' -> North
+    'L' -> South
+turn East turn =
+  case turn of
+    'R' -> South
+    'L' -> North
+turn South turn =
+  case turn of
+    'R' -> West
+    'L' -> East
+
+move North count row col = (row - count, col)
+move South count row col = (row + count, col)
+move East count row col = (row, col + count)
+move West count row col = (row, col - count)

2016/day1-haskell/input.txt

@@ -0,0 +1 @@
+R3, R1, R4, L4, R3, R1, R1, L3, L5, L5, L3, R1, R4, L2, L1, R3, L3, R2, R1, R1, L5, L2, L1, R2, L4, R1, L2, L4, R2, R2, L2, L4, L3, R1, R4, R3, L1, R1, L5, R4, L2, R185, L2, R4, R49, L3, L4, R5, R1, R1, L1, L1, R2, L1, L4, R4, R5, R4, L3, L5, R1, R71, L1, R1, R186, L5, L2, R5, R4, R1, L5, L2, R3, R2, R5, R5, R4, R1, R4, R2, L1, R4, L1, L4, L5, L4, R4, R5, R1, L2, L4, L1, L5, L3, L5, R2, L5, R4, L4, R3, R3, R1, R4, L1, L2, R2, L1, R4, R2, R2, R5, R2, R5, L1, R1, L4, R5, R4, R2, R4, L5, R3, R2, R5, R3, L3, L5, L4, L3, L2, L2, R3, R2, L1, L1, L5, R1, L3, R3, R4, R5, L3, L5, R1, L3, L5, L5, L2, R1, L3, L1, L3, R4, L1, R3, L2, L2, R3, R3, R4, R4, R1, L4, R1, L5

README.md

@@ -42,6 +42,7 @@ go get github.com/teivah/[email protected]
 
 ### 2023
 
+* [Day 1](https://adventofcode.com/2016/day/1): [Haskell](2016/day1-haskell/Main.hs)
 * [Day 3](https://adventofcode.com/2015/day/3): [Haskell](2015/day3-haskell/Main.hs)
 * [Day 24](https://adventofcode.com/2023/day/24): [Go](2023/day24-go/main.go)
 * [Day 23](https://adventofcode.com/2023/day/23): [Go](2023/day23-go/main.go)