Day 11 Part 1

2024/11/puzzle.php

@@ -0,0 +1,28 @@
+<?php
+
+$inputStream = fopen('input.txt', 'r+');
+$stones = explode(' ', trim(fgets($inputStream)));
+echo implode(' ', $stones).PHP_EOL;
+$blinks = 25;
+for ($blink = 1; $blink <= $blinks; $blink++) {
+    $transformed = [];
+    $splits = 0;
+    foreach ($stones as $position => $engraving) {
+        if ($engraving === '0') {
+            $transformed[$position + $splits] = 1;
+        } elseif (($length = strlen($engraving)) % 2 === 0) {
+            $first = substr($engraving, 0, $length / 2);
+            $second = substr($engraving, ($length / 2));
+            array_splice($transformed, $position + $splits, 1, [(string) (int) $first, (string) (int) $second]);
+            ++$splits;
+        } else {
+            $transformed[$position + $splits] = $engraving * 2024;
+        }
+    }
+    $stones = $transformed;
+    echo "Blink $blink: ".count($stones).PHP_EOL;
+//    echo implode(' ', $stones).PHP_EOL.PHP_EOL;
+}
+
+echo "FINAL: ".count($stones).PHP_EOL;
+