Year 2015 Day 14

Author: maneatingape

README.md

@@ -223,3 +223,4 @@ The minimal SBT project provides:
 | 11 | [Corporate Policy](https://adventofcode.com/2015/day/11) | [Source](src/main/scala/AdventOfCode2015/Day11.scala) |
 | 12 | [JSAbacusFramework.io](https://adventofcode.com/2015/day/12) | [Source](src/main/scala/AdventOfCode2015/Day12.scala) |
 | 13 | [Knights of the Dinner Table](https://adventofcode.com/2015/day/13) | [Source](src/main/scala/AdventOfCode2015/Day13.scala) |
+| 14 | [Reindeer Olympics](https://adventofcode.com/2015/day/14) | [Source](src/main/scala/AdventOfCode2015/Day14.scala) |

src/main/resources/AdventOfCode2015/Day14.txt

@@ -0,0 +1,9 @@
+Vixen can fly 8 km/s for 8 seconds, but then must rest for 53 seconds.
+Blitzen can fly 13 km/s for 4 seconds, but then must rest for 49 seconds.
+Rudolph can fly 20 km/s for 7 seconds, but then must rest for 132 seconds.
+Cupid can fly 12 km/s for 4 seconds, but then must rest for 43 seconds.
+Donner can fly 9 km/s for 5 seconds, but then must rest for 38 seconds.
+Dasher can fly 10 km/s for 4 seconds, but then must rest for 37 seconds.
+Comet can fly 3 km/s for 37 seconds, but then must rest for 76 seconds.
+Prancer can fly 9 km/s for 12 seconds, but then must rest for 97 seconds.
+Dancer can fly 37 km/s for 1 seconds, but then must rest for 36 seconds.

src/main/scala/AdventOfCode2015/Day14.scala

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+package AdventOfCode2015
+
+object Day14:
+  case class Reindeer(speed: Int, fly: Int, rest: Int):
+    def distance(time: Int): Int =
+      val total = fly + rest
+      val complete = time / total
+      val partial = (time % total).min(fly)
+      speed * (complete * fly + partial)
+
+  def parse(input: Seq[String]): Seq[Reindeer] = input.map { line =>
+    val Array(speed, fly, rest) = line.split("\\D+").tail.map(_.toInt)
+    Reindeer(speed, fly, rest)
+  }
+
+  def part1(input: Seq[String], time: Int): Int = parse(input).map(_.distance(time)).max
+
+  def part2(input: Seq[String], time: Int): Int =
+    val reindeer = parse(input)
+    (1 to time)
+      .map(time => reindeer.map(_.distance(time)))
+      .map(state => state.map(d => if d == state.max then 1 else 0))
+      .transpose.map(_.sum).max
+
+  def main(args: Array[String]): Unit =
+    val data = io.Source.fromResource("AdventOfCode2015/Day14.txt").getLines().toSeq
+    println(part1(data, 2503))
+    println(part2(data, 2503))

src/test/scala/AdventOfCode2015/Day14Suite.scala

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+package AdventOfCode2015
+
+import org.scalatest.funsuite.AnyFunSuite
+
+class Day14Suite extends AnyFunSuite:
+  val sample = Seq(
+    "Comet can fly 14 km/s for 10 seconds, but then must rest for 127 seconds.",
+    "Dancer can fly 16 km/s for 11 seconds, but then must rest for 162 seconds.")
+
+  test("Part 1 should handle sample input correctly") {
+    assert(Day14.part1(sample, 1000) == 1120)
+  }
+
+  test("Part 2 should handle sample input correctly") {
+    assert(Day14.part2(sample, 1000) == 689)
+  }