feat: 2015 day 16

2015/day16.scala

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+package y2015.day16
+
+import prelude.*
+
+import cats.parse.Parser
+import cats.parse.Parser.*
+import cats.parse.Rfc5234.{digit, alpha}
+
+type Clue = Map[String, Int]
+
+val number: Parser[Int] =
+  digit.rep.string.map(_.toInt)
+
+val ident: Parser[String] =
+  alpha.rep.string
+
+val id: Parser[Int] =
+  string("Sue ") *> number <* string(": ")
+
+val clue: Parser[(String, Int)] =
+  (ident <* string(": ")) ~ number
+
+val clues: Parser[Clue] =
+  clue.repSep(string(", ")).map(_.toList.toMap)
+
+val aunt: Parser[Aunt] =
+  (id ~ clues).map { (id, clues) => Aunt(id, clues) }
+
+case class Aunt(id: Int, info: Clue):
+  def matchEq(known: Clue): Boolean =
+    zipAllByKey(info, known).values.forall { (a, b) => a == b }
+
+  def matchRange(known: Clue): Boolean =
+    zipAllByKey(info, known).forall {
+      case (k, v) if Set("cats", "trees") contains k           => v._1 > v._2
+      case (k, v) if Set("pomeranians", "goldfish") contains k => v._1 < v._2
+      case (k, v)                                              => v._1 == v._2
+    }
+
+val known = Map(
+  "children" -> 3,
+  "cats" -> 7,
+  "samoyeds" -> 2,
+  "pomeranians" -> 3,
+  "akitas" -> 0,
+  "vizslas" -> 0,
+  "goldfish" -> 5,
+  "trees" -> 3,
+  "cars" -> 2,
+  "perfumes" -> 1,
+)
+
+def part1(xs: Iterable[Aunt]) =
+  xs.find(_.matchEq(known)).get.id
+
+def part2(xs: Iterable[Aunt]) =
+  xs.find(_.matchRange(known)).get.id
+
+@main def main() =
+  val input = fromFile(".cache/2015/16.txt").getLines
+    .map(_.trim)
+    .flatMap(aunt.parseAll)
+    .toSeq
+
+  println(part1(input))
+  println(part2(input))

2015/day16.test.scala

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+package y2015.day16
+
+import prelude.*
+import munit.FunSuite
+import y2015.day16.*
+
+val auntRight = Aunt(1, Map("goldfish" -> 9, "cars" -> 0, "samoyeds" -> 9))
+val auntEmpty = Aunt(1, Map.empty)
+
+class ParserTests extends FunSuite:
+  assertEquals(
+    aunt.parseAll("Sue 1: goldfish: 9, cars: 0, samoyeds: 9"),
+    Right(auntRight),
+  )
+
+class MatchEqTests extends FunSuite:
+  val clue = Map("goldfish" -> 9, "cars" -> 0, "samoyeds" -> 9)
+
+  test("empty"):
+    assertEquals(auntEmpty.matchEq(clue), true)
+
+  test("matches"):
+    assertEquals(auntRight.matchEq(clue), true)
+
+  test("mismatches"):
+    assertEquals(auntRight.matchEq(clue + ("goldfish" -> 10)), false)
+
+  test("unknown clue"):
+    assertEquals(auntRight.matchEq(clue + ("unknown" -> 10)), true)
+
+class MatchRangeTests extends FunSuite:
+  val auntRight =
+    Aunt(1, Map("cats" -> 6, "trees" -> 6, "pomeranians" -> 4, "goldfish" -> 4))
+
+  val clue =
+    Map("cats" -> 5, "trees" -> 5, "pomeranians" -> 5, "goldfish" -> 5)
+
+  test("empty"):
+    assertEquals(auntEmpty.matchRange(clue), true)
+
+  test("matches"):
+    assertEquals(auntRight.matchRange(clue), true)
+
+  test("cats"):
+    assertEquals(auntRight.matchRange(clue + ("cats" -> 10)), false)
+    assertEquals(auntRight.matchRange(clue + ("cats" -> 5)), true)
+
+  test("trees"):
+    assertEquals(auntRight.matchRange(clue + ("trees" -> 10)), false)
+    assertEquals(auntRight.matchRange(clue + ("trees" -> 5)), true)
+
+  test("pomeranians"):
+    assertEquals(auntRight.matchRange(clue + ("pomeranians" -> 10)), true)
+    assertEquals(auntRight.matchRange(clue + ("pomeranians" -> 4)), false)
+
+  test("goldfish"):
+    assertEquals(auntRight.matchRange(clue + ("goldfish" -> 10)), true)
+    assertEquals(auntRight.matchRange(clue + ("goldfish" -> 4)), false)
+
+  test("unknown clue"):
+    assertEquals(auntRight.matchRange(clue + ("unknown" -> 10)), true)