Advent of Code 2024 - Day 1

flake.nix

@@ -83,6 +83,9 @@
           gofumpt
 
           nodejs
+
+          python310
+          black
         ]);
 
         shellHook = ''

src/advent_of_code/2024/1.hs

@@ -0,0 +1,38 @@
+-- https://adventofcode.com/2024/day/1
+
+import           Data.List
+import           GHC.IO
+
+input :: FilePath
+input = "src/advent_of_code/2024/1.input"
+
+entries :: ([Int], [Int])
+entries = unzip $ map parse' $ unsafePerformIO $ lines <$> readFile input
+
+main :: IO ()
+main = do
+  entries <- lines <$> readFile input
+  print "Advent of Code 2024 - Day 1"
+
+  print $ "Part 1: " <> show (solveP1 $ unzip $ map parse' entries)
+  print $ "Part 2: " <> show (solveP2 $ unzip $ map parse' entries)
+
+parse' :: String -> (Int, Int)
+parse' str = (read l, read r)
+  where
+    l = take' str
+    r = reverse $ take' $ reverse str
+    take' = takeWhile (/= ' ')
+
+solveP1 :: ([Int], [Int]) -> Int
+solveP1 (as, bs) = sum $ zipWith (\i j -> abs (i - j)) as' bs'
+  where
+    as' = sort as
+    bs' = sort bs
+
+solveP2 :: ([Int], [Int]) -> Int
+solveP2 (as, bs) = sum $ zipWith (*) as (map (f bs) as)
+  where
+    f :: [Int] -> Int -> Int
+    f bs a = length $ elemIndices a bs
+

src/advent_of_code/2024/1f.input

@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3

src/projectEuler/question1.hs

@@ -5,9 +5,6 @@ The sum of these multiples is 23.
 
 Find the sum of all the multiples of 3 or 5 below 1000.
 -}
-{-# OPTIONS_GHC -Wno-unrecognised-pragmas #-}
-{-# HLINT ignore "Use sum" #-}
-
 module Main where
 
 import           Data.List (union)
@@ -16,26 +13,13 @@ main :: IO ()
 main = print ans
 
 ans :: Integer
-ans = sum $ allNumbersUnder 1000
-
-sum' :: Num a => [a] -> a
-sum' = foldl (+) 0
-
-isMultipleOf :: Integral a => a -> a -> Bool
-isMultipleOf n x = x `rem` n == 0
-
-all3sUnder :: Integral a => a -> [a]
-all3sUnder n = filter (isMultipleOf 3) [1..n-1]
-all5sUnder :: Integral a => a -> [a]
-all5sUnder n = filter (isMultipleOf 5) [1..n-1]
-
-allXsUnderN :: Integral a => a -> a -> [a]
-allXsUnderN x n = filter (isMultipleOf x) [1..n-1]
-
-allNumbersUnder :: Integral a => a -> [a]
-allNumbersUnder l = allXsUnderN 3 l <> allXsUnderN 5 l
-
+ans = sum (_3s <> _5s)
 
+_3s :: [Integer]
 _3s = [3,6..999]
+
+_5s :: [Integer]
 _5s = [5,10..999]
+
+solution :: Integer
 solution = sum $ union _3s _5s

src/python/2.py

@@ -0,0 +1,28 @@
+fibs2 = [1, 2, 3, 5, 8, 13]
+
+i = 1
+j = 2
+b = 0
+n = 4000000
+fibs = []
+fibs.append(i)
+fibs.append(j)
+
+while b < n:
+    b = i + j
+    if b < n:
+        fibs.append(b)
+    else:
+        fibs
+    i = j
+    j = b
+
+count = 0
+for fib in fibs:
+    if (fib % 2) == 0:
+        count += fib
+    else:
+        count += 0
+
+print(count)
+