Day 02

src/main/scala/Main.scala

@@ -3,7 +3,8 @@ package dev.ctsk.aoc
 import dev.ctsk.aoc.days._
 
 val solvers = Map[Int, Solver](
-  1 -> Day01
+  1 -> Day01,
+  2 -> Day02
 )
 
 @main def main(day: String, input: String): Unit =

src/main/scala/days/Day02.scala

@@ -0,0 +1,35 @@
+package dev.ctsk.aoc.days
+
+import dev.ctsk.aoc._
+
+object Day02 extends Solver(2):
+  def pre(input: String): List[List[Int]] =
+    io.Source
+      .fromFile(input)
+      .getLines()
+      .map(line => line.split(" ").map(_.toInt).toList)
+      .toList
+
+  def valid(list: List[Int]): Boolean =
+    val isSorted = (list.sorted == list || list.sorted.reverse == list)
+    val notTooLarge = list.sliding(2).map(x => (x(1) - x(0)).abs).forall(_ <= 3)
+    val notTooSmall = list.sliding(2).map(x => (x(1) - x(0)).abs).forall(_ >= 1)
+    isSorted && notTooLarge && notTooSmall
+
+  def part1(lists: List[List[Int]]): Int = lists.count(valid)
+
+  def part2(lists: List[List[Int]]): Int =
+    lists.count(list =>
+      list.indices.exists(i => valid(list.take(i) ++ list.drop(i + 1)))
+    )
+
+  def run(input: String): (Timings, Solution) =
+
+    val (pre_time, pre_input) = timed { pre(input) }
+    val (p1_time, p1_solution) = timed { part1(pre_input) }
+    val (p2_time, p2_solution) = timed { part2(pre_input) }
+
+    (
+      Timings(pre_time, p1_time, p2_time),
+      Solution(Int.box(p1_solution), Int.box(p2_solution))
+    )