Day24 part1

2020-12-24 12:48:30 +01:00
parent 0b1ae6e334
commit 23cb05ad27
2 changed files with 471 additions and 0 deletions
@@ -0,0 +1,52 @@
+package be.vandewalleh.aoc.days
+
+import be.vandewalleh.aoc.utils.input.Day
+import be.vandewalleh.aoc.utils.input.Input
+import be.vandewalleh.aoc.utils.input.Lines
+import be.vandewalleh.aoc.utils.input.createDay
+import org.eclipse.collections.api.factory.Bags
+
+@Day(24)
+class Day24(@Lines val input: Input<List<String>>) {
+
+    private enum class Direction(vararg coordinates: Int) {
+        E(1, -1, 0),
+        SE(0, -1, 1),
+        SW(-1, 0, 1),
+        W(-1, 1, 0),
+        NW(0, 1, -1),
+        NE(1, 0, -1);
+
+        val coordinates = coordinates
+    }
+
+    private data class Tile(val directions: List<Direction>)
+
+    private fun parseTile(line: String): Tile {
+        val re = "e|se|sw|w|nw|ne".toRegex()
+        val directions = re.findAll(line).flatMap { it.groupValues }.map { Direction.valueOf(it.toUpperCase()) }
+        return Tile(directions.toList())
+    }
+
+    fun part1() {
+        val tiles = input.value.map { parseTile(it) }
+        val bag = Bags.mutable.empty<List<Int>>()
+        for (tile in tiles) {
+            val encountered = tile.directions
+                .map { it.coordinates }
+                .reduce { acc, ints -> intArrayOf(acc[0] + ints[0], acc[1] + ints[1], acc[2] + ints[2]) }
+                .toList()
+            bag.add(encountered)
+        }
+        println(bag.selectByOccurrences { it % 2 == 1 }.size)
+    }
+
+    fun part2() {
+
+    }
+}
+
+fun main() = with(createDay<Day24>()) {
+    println(part1())
+    println(part2())
+}