feat(2025): day 06 source code (#897)

Author: scarf005

2025/src/day06.scala

@@ -0,0 +1,39 @@
+package day06
+
+import locations.Directory.currentDir
+import inputs.Input.loadFileSync
+
+@main def part1: Unit =
+  println(s"The solution is ${part1(loadInput())}")
+
+@main def part2: Unit =
+  println(s"The solution is ${part2(loadInput())}")
+
+def loadInput(): String = loadFileSync(s"$currentDir/../input/day06")
+
+extension [A](xs: IterableOnce[A])
+  inline def splitBy(sep: A) =
+    val (b, cur) = (Vector.newBuilder[Vector[A]], Vector.newBuilder[A])
+    for e <- xs.iterator do
+      if e != sep then cur += e else { b += cur.result(); cur.clear() }
+    (b += cur.result()).result()
+
+extension (xs: Iterator[(symbol: String, nums: IterableOnce[String])])
+  def calculate: Long = xs.iterator.collect {
+    case ("*", nums) => nums.iterator.map(_.toLong).product
+    case ("+", nums) => nums.iterator.map(_.toLong).sum
+  }.sum
+
+def part1(input: String): Long = input.linesIterator.toVector
+  .map(_.trim.split(raw"\s+"))
+  .transpose
+  .iterator
+  .map { col => (col.last, col.view.init) }
+  .calculate
+
+def part2(input: String): Long =
+  val lines = input.linesIterator.toVector
+  val ops = lines.last.split(raw"\s+").iterator
+  val xss = lines.init.transpose.map(_.mkString.trim).splitBy("")
+
+  (ops zip xss).calculate