[2025/10] Factory (Part 1)

Author: pfolta

README.md

@@ -29,7 +29,7 @@
 |     2022 |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★    |   ★    |   ★    |   ★    |        |        |        |        |        |        |        |   ☆    |        |        |        |   ☆    |    28 |
 |     2023 |   ★   |   ★   |   ★   |   ★   |   ☆   |   ★   |   ☆   |       |       |        |        |        |        |        |        |        |        |        |        |        |        |        |        |        |        |    12 |
 |     2024 |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★    |   ★    |   ★    |   ★    |   ★    |        |   ☆    |   ★    |   ★    |   ★    |   ★    |        |   ★    |        |        |   ☆    |    40 |
-|     2025 |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |        |   ★    |        |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |    20 |
+|     2025 |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ★   |   ☆    |   ★    |        |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |   –    |    21 |
 
 ## 🛷 How to run
 
@@ -215,6 +215,7 @@ e.g. `HandyHaversacks`)*
 |                                           |   7 | [Laboratories](https://adventofcode.com/2025/day/7)                                                    | [[Code](src/main/kotlin/adventofcode/year2025/Day07Laboratories.kt)] [[Test](src/test/kotlin/adventofcode/year2025/Day07LaboratoriesSpec.kt)]                                           | `1711`                 | `36706966158365`                                 |
 |                                           |   8 | [Playground](https://adventofcode.com/2025/day/8)                                                      | [[Code](src/main/kotlin/adventofcode/year2025/Day08Playground.kt)] [[Test](src/test/kotlin/adventofcode/year2025/Day08PlaygroundSpec.kt)]                                               | `135169`               | `302133440`                                      |
 |                                           |   9 | [Movie Theater](https://adventofcode.com/2025/day/9)                                                   | [[Code](src/main/kotlin/adventofcode/year2025/Day09MovieTheater.kt)] [[Test](src/test/kotlin/adventofcode/year2025/Day09MovieTheaterSpec.kt)]                                           | `4777409595`           | `1473551379`                                     |
+|                                           |  10 | [Factory](https://adventofcode.com/2025/day/10)                                                        | [[Code](src/main/kotlin/adventofcode/year2025/Day10Factory.kt)] [[Test](src/test/kotlin/adventofcode/year2025/Day10FactorySpec.kt)]                                                     | `517`                  |                                                  |
 |                                           |  11 | [Reactor](https://adventofcode.com/2025/day/11)                                                        | [[Code](src/main/kotlin/adventofcode/year2025/Day11Reactor.kt)] [[Test](src/test/kotlin/adventofcode/year2025/Day11ReactorSpec.kt)]                                                     | `699`                  | `388893655378800`                                |
 
 ## 🕯️ Useful commands

src/main/kotlin/adventofcode/year2025/Day10Factory.kt

@@ -0,0 +1,77 @@
+package adventofcode.year2025
+
+import adventofcode.Puzzle
+import adventofcode.PuzzleInput
+import adventofcode.common.Permutations.powersets
+
+class Day10Factory(
+    customInput: PuzzleInput? = null,
+) : Puzzle(customInput) {
+    private fun parseInput() = input.lines().map(Machine::invoke)
+
+    override fun partOne() =
+        parseInput()
+            .sumOf { machine ->
+                machine
+                    .buttons
+                    .powersets()
+                    .sortedBy { combination -> combination.size }
+                    .first { combination ->
+                        combination.fold(List(machine.lights.size) { false }) { lights, buttons ->
+                            lights.mapIndexed { index, light ->
+                                when (index in buttons) {
+                                    true -> !light
+                                    else -> light
+                                }
+                            }
+                        } == machine.lights
+                    }.size
+            }
+
+    companion object {
+        private data class Machine(
+            val lights: List<Boolean>,
+            val buttons: List<List<Int>>,
+            val joltages: List<Int>,
+        ) {
+            companion object {
+                operator fun invoke(input: String): Machine {
+                    val lights =
+                        input
+                            .substringAfter("[")
+                            .substringBefore("]")
+                            .split("")
+                            .filter(String::isNotEmpty)
+                            .map { light ->
+                                when (light.single()) {
+                                    '#' -> true
+                                    else -> false
+                                }
+                            }
+
+                    val buttons =
+                        input
+                            .substringAfter(" ")
+                            .substringBefore(" {")
+                            .split(" ")
+                            .map { buttons ->
+                                buttons
+                                    .replace("(", "")
+                                    .replace(")", "")
+                                    .split(",")
+                                    .map(String::toInt)
+                            }
+
+                    val joltages =
+                        input
+                            .substringAfter("{")
+                            .substringBefore("}")
+                            .split(",")
+                            .map(String::toInt)
+
+                    return Machine(lights, buttons, joltages)
+                }
+            }
+        }
+    }
+}