✨ Finit les part 1 du jour 2 et 3

Ouin, pas le temps de faire les part 2 😭

day_2/part_1.php

@@ -0,0 +1,52 @@
+<?php
+
+$reports = array_filter(explode("\n", file_get_contents(__DIR__.'/input.txt')), static fn($line) =>!empty($line));
+
+$number_of_safe_reports = 0;
+function is_report_safe(string $report)
+{
+    $levels = explode(' ', $report);
+    $current_number = null;
+    $current_way = null;
+    foreach ($levels as $level) {
+        if ($current_number === null) {
+            $current_number = $level;
+        } else {
+            if ($current_number === $level) {
+                return false;
+            }
+            if ($current_number > $level) {
+                if ($current_number - $level > 3) {
+                    return false;
+                }
+                if ($current_way === null) {
+                    $current_way = 'd';
+                } elseif ($current_way !== 'd') {
+                    return false;
+                }
+            }
+            if ($current_number < $level) {
+                if ($level - $current_number > 3) {
+                    return false;
+                }
+                if ($current_way === null) {
+                    $current_way = 'a';
+                } elseif ($current_way !== 'a') {
+                    return false;
+                }
+            }
+            $current_number = $level;
+        }
+    }
+
+    return true;
+}
+
+foreach ($reports as $report) {
+    if (is_report_safe($report)) {
+        $number_of_safe_reports++;
+    }
+}
+
+echo sprintf('Number of safe reports : %u', $number_of_safe_reports);
+exit;

day_3/part_1.php

@@ -0,0 +1,8 @@
+<?php
+
+$instruction = file_get_contents(__DIR__.'/input.txt');
+
+preg_match_all('/mul\((\d+),(\d+)\)/', $instruction, $muls, PREG_SET_ORDER);
+
+echo array_sum(array_map(static fn($mul) => $mul[1]*$mul[2], $muls));
+exit;