Faster parsing

Author: maneatingape

README.md

@@ -110,7 +110,7 @@ pie
 | 19 | [Not Enough Minerals](https://adventofcode.com/2022/day/19) | [Source](src/year2022/day19.rs) | 407 |
 | 20 | [Grove Positioning System](https://adventofcode.com/2022/day/20) | [Source](src/year2022/day20.rs) | 5067 |
 | 21 | [Monkey Math](https://adventofcode.com/2022/day/21) | [Source](src/year2022/day21.rs) | 61 |
-| 22 | [Monkey Map](https://adventofcode.com/2022/day/22) | [Source](src/year2022/day22.rs) | 132 |
+| 22 | [Monkey Map](https://adventofcode.com/2022/day/22) | [Source](src/year2022/day22.rs) | 55 |
 | 23 | [Unstable Diffusion](https://adventofcode.com/2022/day/23) | [Source](src/year2022/day23.rs) | 2017 |
 | 24 | [Blizzard Basin](https://adventofcode.com/2022/day/24) | [Source](src/year2022/day24.rs) | 80 |
 | 25 | [Full of Hot Air](https://adventofcode.com/2022/day/25) | [Source](src/year2022/day25.rs) | 3 |

src/year2022/day22.rs

@@ -208,14 +208,19 @@ fn parse_grid(input: &str) -> Grid {
 
 fn parse_moves(input: &str) -> Vec<Move> {
     let mut moves = Vec::new();
+    let mut numbers = input.iter_unsigned();
+    let mut letters = input.bytes().filter(u8::is_ascii_uppercase);
 
-    for token in input.replace('L', " L ").replace('R', " R ").trim().split(' ') {
-        let next = match token {
-            "L" => Move::Left,
-            "R" => Move::Right,
-            n => Move::Forward(n.unsigned()),
+    loop {
+        let Some(n) = numbers.next() else {
+            break;
         };
-        moves.push(next);
+        moves.push(Move::Forward(n));
+
+        let Some(d) = letters.next() else {
+            break;
+        };
+        moves.push(if d == b'L' { Move::Left } else { Move::Right });
     }
 
     moves