From 1e84b70b7aa0d6c912e8f3b194a7b4b539c47934 Mon Sep 17 00:00:00 2001
From: Clement Desmidt <clement@desmidt.fr>
Date: Tue, 6 Dec 2022 09:47:09 +0100
Subject: [PATCH] :sparkles: Finit le jour 3

---
 day_3/part_1.php | 15 +++++++++++++++
 day_3/part_2.php | 17 +++++++++++++++++
 2 files changed, 32 insertions(+)
 create mode 100644 day_3/part_1.php
 create mode 100644 day_3/part_2.php

diff --git a/day_3/part_1.php b/day_3/part_1.php
new file mode 100644
index 0000000..ac7824e
--- /dev/null
+++ b/day_3/part_1.php
@@ -0,0 +1,15 @@
+<?php
+
+$rucksacks = explode("\n", file_get_contents('./input.txt'));
+
+$lettersToNumbers = array_merge(range('a', 'z'), range('A', 'Z'));
+
+echo array_sum(
+    array_map(
+        static function($rucksack) use ($lettersToNumbers) {
+            [$f, $s] = array_map('str_split', str_split($rucksack, strlen($rucksack)/2));
+            return array_search(current(array_intersect($f, $s)), $lettersToNumbers, true) + 1;
+        },
+        $rucksacks
+    )
+);
diff --git a/day_3/part_2.php b/day_3/part_2.php
new file mode 100644
index 0000000..fabda76
--- /dev/null
+++ b/day_3/part_2.php
@@ -0,0 +1,17 @@
+<?php
+
+$rucksacks = explode("\n", file_get_contents('./input.txt'));
+
+$lettersToNumbers = array_merge(range('a', 'z'), range('A', 'Z'));
+
+$groups = array_chunk($rucksacks, 3);
+
+echo array_sum(
+    array_map(
+        static function($rucksacks) use ($lettersToNumbers) {
+            [$f, $s, $t] = array_map('str_split', $rucksacks);
+            return array_search(current(array_intersect($f, $s, $t)), $lettersToNumbers, true) + 1;
+        },
+        $groups
+    )
+);