Day 13 part 2

2024/src/main/kotlin/day13.kt

@@ -3,32 +3,48 @@ val regex = "Button A: X\\+(\\d+), Y\\+(\\d+)\nButton B: X\\+(\\d+), Y\\+(\\d+)\
 data class Machine(
     val buttonA: Grid.Coordinate,
     val buttonB: Grid.Coordinate,
-    val price: Grid.Coordinate
+    val priceX: Long,
+    val priceY: Long
 ) {
 
-    fun solveA(b: Int) = (price.x - b * buttonB.x) / buttonA.x
-    fun solveB() = (price.y * buttonA.x - price.x * buttonA.y) / (buttonA.x * buttonB.y - buttonA.y * buttonB.x)
+    fun solveA(b: Long) = (priceX - b * buttonB.x) / buttonA.x
+    fun solveB() = (priceY * buttonA.x - priceX * buttonA.y) / (buttonA.x * buttonB.y - buttonA.y * buttonB.x)
 
-    fun solve(): Pair<Int, Int>? {
+    fun solve(): Pair<Long, Long>? {
         val b = solveB()
         val a = solveA(b)
 
-        return Pair(a, b).takeIf { (a * buttonA.x + b * buttonB.x) == price.x && (a * buttonA.y + b * buttonB.y) == price.y }
+        return Pair(
+            a,
+            b
+        ).takeIf { (a * buttonA.x + b * buttonB.x) == priceX && (a * buttonA.y + b * buttonB.y) == priceY }
     }
 }
 
 fun main() {
-    val part1 = regex.findAll(readInputString("day13.txt"))
+    val machines = regex.findAll(readInputString("day13.txt"))
         .map {
             Machine(
                 buttonA = Grid.Coordinate(it.groupValues[1].toInt(), it.groupValues[2].toInt()),
                 buttonB = Grid.Coordinate(it.groupValues[3].toInt(), it.groupValues[4].toInt()),
-                price = Grid.Coordinate(it.groupValues[5].toInt(), it.groupValues[6].toInt()),
+                priceX = it.groupValues[5].toLong(),
+                priceY = it.groupValues[6].toLong()
             )
         }
-        .mapNotNull { it.solve() }
+        .toList()
+
+    val part1 = machines.mapNotNull { it.solve() }
         .sumOf { (a, b) -> 3 * a + b }
 
     println("Part 1: $part1")
 
+    val part2 = machines.map {
+        it.copy(
+            priceX = it.priceX + 10000000000000,
+            priceY = it.priceY + 10000000000000
+        )
+    }.mapNotNull { it.solve() }
+        .sumOf { (a, b) -> 3 * a + b }
+
+    println("Part 2: $part2")
 }