From b2e1d5f20cb21d4fdd4f0aca9ccef6401e9d8ddb Mon Sep 17 00:00:00 2001
From: Viacheslav Slinko <me@vslinko.ru>
Date: Sat, 21 Dec 2024 21:59:01 +0300
Subject: [PATCH] day21

---
 src/day21.rs | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/src/day21.rs b/src/day21.rs
index a7353f4..58cadf5 100644
--- a/src/day21.rs
+++ b/src/day21.rs
@@ -1,5 +1,5 @@
 const fn numeric_keypad_index(from: u8, to: u8) -> usize {
-    // 18 is minimum multiple that creates a unique index for each pair of buttons
+    // 18 is minimum multiplier that provides a unique index for each pair of buttons
     (from as usize) - 48 + ((to as usize) - 48) * 18
 }
 
@@ -261,25 +261,21 @@ const LUT2: [u64; LUT_SIZE] = {
     lut
 };
 
+#[rustfmt::skip]
 unsafe fn parse_num(n: &[u8]) -> u64 {
-    (*n.get_unchecked(0) as u64) * 100
-        + (*n.get_unchecked(1) as u64) * 10
-        + (*n.get_unchecked(2) as u64)
-        - 5328
+    (*n.get_unchecked(0) as u64) * 100 +
+    (*n.get_unchecked(1) as u64) * 10 +
+    (*n.get_unchecked(2) as u64) - 5328
 }
 
+#[rustfmt::skip]
 unsafe fn calculate_code(moves: &[u64; LUT_SIZE], code: &[u8]) -> u64 {
-    parse_num(code)
-        * (moves.get_unchecked(numeric_keypad_index(b'A', *code.get_unchecked(0)))
-            + moves.get_unchecked(numeric_keypad_index(
-                *code.get_unchecked(0),
-                *code.get_unchecked(1),
-            ))
-            + moves.get_unchecked(numeric_keypad_index(
-                *code.get_unchecked(1),
-                *code.get_unchecked(2),
-            ))
-            + moves.get_unchecked(numeric_keypad_index(*code.get_unchecked(2), b'A')))
+    parse_num(code) * (
+        moves.get_unchecked(numeric_keypad_index(b'A', *code.get_unchecked(0))) +
+        moves.get_unchecked(numeric_keypad_index(*code.get_unchecked(0), *code.get_unchecked(1))) +
+        moves.get_unchecked(numeric_keypad_index(*code.get_unchecked(1), *code.get_unchecked(2))) +
+        moves.get_unchecked(numeric_keypad_index(*code.get_unchecked(2), b'A'))
+    )
 }
 
 pub fn part1(input: &str) -> u64 {