✨ Finit le jour 6

day_6/part_2.php

@@ -0,0 +1,24 @@
+<?php
+
+$timers = array_map('intval', explode(',', file_get_contents('./input.txt')));
+
+echo sprintf('Initial state: %s', implode(',', $timers));
+
+$timers = array_count_values($timers);
+
+for ($i = 0; $i < 256; $i++) {
+    $tmp = array_fill(0, 9, 0);
+    foreach ($timers as $number => $count) {
+        if($number > 0) {
+            $tmp[$number-1] += $count;
+        } else {
+            $tmp[6] += $count;
+            $tmp[8] += $count;
+        }
+    }
+    $timers = $tmp;
+
+    echo sprintf('After %u day(s): %s with %u zero%s', $i + 1, array_sum($timers), (array_key_exists(0, $timers) ? $timers[0] : 0), "\n");
+}
+
+echo array_sum($timers);