Year 2015 Day 15

Author: maneatingape

README.md

@@ -224,3 +224,4 @@ The minimal SBT project provides:
 | 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) |
+| 15 | [Science for Hungry People](https://adventofcode.com/2015/day/15) | [Source](src/main/scala/AdventOfCode2015/Day15.scala) |

src/main/resources/AdventOfCode2015/Day15.txt

@@ -0,0 +1,4 @@
+Sugar: capacity 3, durability 0, flavor 0, texture -3, calories 2
+Sprinkles: capacity -3, durability 3, flavor 0, texture 0, calories 9
+Candy: capacity -1, durability 0, flavor 4, texture 0, calories 1
+Chocolate: capacity 0, durability 0, flavor -2, texture 2, calories 8

src/main/scala/AdventOfCode2015/Day15.scala

@@ -0,0 +1,22 @@
+package AdventOfCode2015
+
+object Day15:
+  def recipes(input: Seq[String]): Iterator[Seq[Int]] =
+    val ingredients = input.map(_.split("[^-\\d]+").tail.map(_.toInt))
+    def range(offset: Int) = Iterator.range(0, 101 - offset)
+    for
+      a <- range(0)
+      b <- range(a)
+      c <- range(a + b)
+      d <- range(a + b + c)
+      if a + b + c + d == 100
+    yield Seq(a, b, c, d).zip(ingredients).map((k, i) => i.map(_ * k)).transpose.map(_.sum.max(0))
+
+  def part1(input: Seq[String]): Int = recipes(input).map(_.init.product).max
+
+  def part2(input: Seq[String]): Int = recipes(input).filter(_.last == 500).map(_.init.product).max
+
+  def main(args: Array[String]): Unit =
+    val data = io.Source.fromResource("AdventOfCode2015/Day15.txt").getLines().toSeq
+    println(part1(data))
+    println(part2(data))

src/test/scala/AdventOfCode2015/Day15Suite.scala

@@ -0,0 +1,6 @@
+package AdventOfCode2015
+
+import org.scalatest.funsuite.AnyFunSuite
+
+class Day15Suite extends AnyFunSuite
+// No unit tests possible