From e00e002cd635f81e9ed6466b1084ce8e7eb76797 Mon Sep 17 00:00:00 2001
From: chrisly42 <chrisly@platon42.de>
Date: Mon, 23 Dec 2024 16:31:11 +0100
Subject: [PATCH] Bitset is even faster (<1 sec).

---
 src/aoc2024/Day22.kt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/aoc2024/Day22.kt b/src/aoc2024/Day22.kt
index 7ef9cd2..ac43a31 100644
--- a/src/aoc2024/Day22.kt
+++ b/src/aoc2024/Day22.kt
@@ -6,6 +6,7 @@ import kotlinx.coroutines.awaitAll
 import kotlinx.coroutines.runBlocking
 import println
 import readInput
+import java.util.*
 
 /*
 --- Day 22: Monkey Market ---
@@ -76,7 +77,7 @@ fun main() {
             var lastd = 0
             var code = 0
             var countDown = 4
-            val seenArray = BooleanArray(19 * 19 * 19 * 19)
+            val seenArray = BitSet(19 * 19 * 19 * 19)
             for (v in priceSequence(it).take(2001)) {
                 val d = v % 10
                 val delta = d - lastd