From 97595af8deaa257cdf7a4dd884077e469ed13bd4 Mon Sep 17 00:00:00 2001
From: Daniele Fucini <dfucini@gmail.com>
Date: Tue, 3 Dec 2024 18:52:51 +0100
Subject: [PATCH] Day 3

---
 Day1/puzzle1.hs |  3 +--
 Day1/puzzle2.hs |  3 +--
 Day2/puzzle1.hs |  3 +--
 Day2/puzzle2.hs |  3 +--
 Day3/puzzle1.hs | 12 ++++++++++++
 Day3/puzzle2.hs | 16 ++++++++++++++++
 6 files changed, 32 insertions(+), 8 deletions(-)
 create mode 100644 Day3/puzzle1.hs
 create mode 100644 Day3/puzzle2.hs

diff --git a/Day1/puzzle1.hs b/Day1/puzzle1.hs
index af5a893..3e5ef60 100644
--- a/Day1/puzzle1.hs
+++ b/Day1/puzzle1.hs
@@ -7,5 +7,4 @@ listDistance xs ys = sum $ map abs $ zipWith (-) (sort xs) (sort ys)
 main = do
     contents <- lines <$> readFile "day1.txt"
     let [x, y] = transpose $ map read . words <$> contents
-        distance = listDistance x y
-    print distance
+    print $ listDistance x y
diff --git a/Day1/puzzle2.hs b/Day1/puzzle2.hs
index c3f7b44..6efe9d9 100644
--- a/Day1/puzzle2.hs
+++ b/Day1/puzzle2.hs
@@ -8,5 +8,4 @@ similarityScore xs ys = let elemsY = [ (head y, length y) | y <- (group . sort)
 main = do
     contents <- lines <$> readFile "day1.txt"
     let [x, y] = transpose $ map read . words <$> contents
-        score = similarityScore x y
-    print score
+    print $ similarityScore x y
diff --git a/Day2/puzzle1.hs b/Day2/puzzle1.hs
index 751737f..eb85305 100644
--- a/Day2/puzzle1.hs
+++ b/Day2/puzzle1.hs
@@ -10,5 +10,4 @@ isSafe xs = (isAscending xs || isDescending xs) && maximum distances <= 3 && min
 main = do
     contents <- lines <$> readFile "day2.txt"
     let reports = map read . words <$> contents
-        safeCount = length $ filter isSafe reports
-    print safeCount
+    print . length $ filter isSafe reports
diff --git a/Day2/puzzle2.hs b/Day2/puzzle2.hs
index f595599..160d86d 100644
--- a/Day2/puzzle2.hs
+++ b/Day2/puzzle2.hs
@@ -15,5 +15,4 @@ removeLevel xs = zipWith (++) ys zs
 main = do
     contents <- lines <$> readFile "day2.txt"
     let reports = map read . words <$> contents
-        safeCount = length . filter (any isSafe) $ map removeLevel reports
-    print safeCount
+    print . length . filter (any isSafe) $ map removeLevel reports
diff --git a/Day3/puzzle1.hs b/Day3/puzzle1.hs
new file mode 100644
index 0000000..4af28bf
--- /dev/null
+++ b/Day3/puzzle1.hs
@@ -0,0 +1,12 @@
+import Data.List.Split (splitOn)
+import Data.Char (isDigit)
+import Text.Regex.TDFA (getAllTextMatches, (=~))
+
+sumMul :: [String] -> Int
+sumMul xs = let vals = map (splitOn "," . filter (`elem` "0123456789,")) xs
+            in  sum $ map (product . map read) vals
+
+main = do
+    contents <- readFile "day3.txt"
+    let mults = getAllTextMatches (contents =~ "mul\\([0-9]+,[0-9]+\\)") :: [String]
+    print $ sumMul mults
diff --git a/Day3/puzzle2.hs b/Day3/puzzle2.hs
new file mode 100644
index 0000000..305fd3e
--- /dev/null
+++ b/Day3/puzzle2.hs
@@ -0,0 +1,16 @@
+import Data.List (isPrefixOf)
+import Data.List.Split (split, splitOn, startsWith)
+import Data.Char (isDigit)
+import Text.Regex.TDFA (getAllTextMatches, (=~))
+
+sumMul :: [String] -> Int
+sumMul xs = let vals = map (splitOn "," . filter (`elem` "0123456789,")) xs
+            in  sum $ map (product . map read) vals
+
+filterDonts :: [String] -> String
+filterDonts = concat . filter (not . isPrefixOf "don't()") . concatMap (split (startsWith "do()"))
+
+main = do
+    contents <- split (startsWith "don't()") <$> readFile "day3.txt"
+    let mults = getAllTextMatches (filterDonts contents =~ "mul\\([0-9]+,[0-9]+\\)") :: [String]
+    print $ sumMul mults