clean up old code where I stored the path for debugging purposes

README.md

@@ -61,9 +61,9 @@ Solutions for [Advent of Code](https://adventofcode.com/) in [Rust](https://www.
 | [Day 20](./src/bin/20.rs) | `323.9µs` | `1.2ms` |
 | [Day 21](./src/bin/21.rs) | `64.1µs` | `494.7µs` |
 | [Day 22](./src/bin/22.rs) | `78.3µs` | `194.8µs` |
-| [Day 23](./src/bin/23.rs) | `329.1µs` | `72.6ms` |
+| [Day 23](./src/bin/23.rs) | `328.8µs` | `69.4ms` |
 
-**Total: 89.54ms**
+**Total: 86.34ms**
 <!--- benchmarking table --->
 
 ---

src/bin/23.rs

@@ -41,16 +41,16 @@ pub fn part_two(input: &str) -> Option<u16> {
         goal = new_goal;
     }
 
-    let mut visited = vec![None; graph.vertices];
-    visited[start] = Some(0);
+    let mut visited = vec![false; graph.vertices];
+    visited[start] = true;
     Some(trimmed_length + part_two_recursive_brute_force(&graph, start, goal, &mut visited, 0))
 }
 
 fn part_two_recursive_brute_force(
     graph: &Graph,
     cur: usize,
     goal: usize,
-    visited: &mut [Option<usize>],
+    visited: &mut [bool],
     so_far: u16,
 ) -> u16 {
     if cur == goal {
@@ -59,12 +59,12 @@ fn part_two_recursive_brute_force(
 
     let mut max = 0;
     for &(neighbor, cost) in &graph.adjacency[cur] {
-        if visited[neighbor].is_none() {
-            visited[neighbor] = Some(cur);
+        if !visited[neighbor] {
+            visited[neighbor] = true;
             let next_so_far =
                 part_two_recursive_brute_force(graph, neighbor, goal, visited, so_far + cost);
             max = max.max(next_so_far);
-            visited[neighbor] = None;
+            visited[neighbor] = false;
         }
     }