2023 - Day 12

2023/src/bin/day12.rs

@@ -1,8 +1,5 @@
 #![feature(test)]
-use std::{
+use std::{collections::{HashMap, hash_map::DefaultHasher}, hash::{Hash, Hasher}};
-    collections::{hash_map::DefaultHasher, HashMap},
-    hash::{Hash, Hasher},
-};
 
 use anyhow::Result;
 use aoc::Solver;
@@ -79,12 +76,7 @@ impl std::fmt::Display for Spring {
 }
 
 // The cache is optional as is slows down part1 by a lot
-fn count_valid(
+fn count_valid(springs: &mut [Spring], list: &[usize], damaged_chain: usize, cache: &mut Option<&mut Cache>) -> usize {
-    springs: &mut [Spring],
-    list: &[usize],
-    damaged_chain: usize,
-    cache: &mut Option<&mut Cache>,
-) -> usize {
     let hash = if let Some(cache) = cache {
         // Calculate the hash manually, otherwise we end up with weird borrows or we have to clone
         // (which is slow)
@@ -105,12 +97,7 @@ fn count_valid(
 
     // We reached the end of the list, no further processing is possible
     let count = if list.is_empty() {
-        if springs
+        if springs.iter().filter(|&spring| spring == &Spring::Damaged).count() > 0 {
-            .iter()
-            .filter(|&spring| spring == &Spring::Damaged)
-            .count()
-            > 0
-        {
             // There are still damaged springs remaining
             0
         } else {
@@ -152,15 +139,10 @@ fn count_valid(
 
                 // Return the sum of both branches
                 a + b
-            }
+            },
             Spring::Damaged => {
-                if damaged_chain + 1 > list[0] {
+                // Add to the damaged chain
-                    // The chain is to long
+                count_valid(&mut springs[1..], list, damaged_chain+1, cache)
-                    0
-                } else {
-                    // Add to the damaged chain
-                    count_valid(&mut springs[1..], list, damaged_chain + 1, cache)
-                }
             }
         }
     };
@@ -212,23 +194,10 @@ impl aoc::Solver for Day {
                         .collect::<Vec<_>>(),
                 )
             })
-            .map(|(springs, list)| {
+            .map(|(springs, list)| (
-                (
+                    [springs.clone(), vec![Spring::Unknown], springs.clone(), vec![Spring::Unknown], springs.clone(), vec![Spring::Unknown], springs.clone(), vec![Spring::Unknown], springs].concat(),
-                    [
+                    [list.clone(), list.clone(), list.clone(), list.clone(), list].concat()
-                        springs.clone(),
+            ))
-                        vec![Spring::Unknown],
-                        springs.clone(),
-                        vec![Spring::Unknown],
-                        springs.clone(),
-                        vec![Spring::Unknown],
-                        springs.clone(),
-                        vec![Spring::Unknown],
-                        springs,
-                    ]
-                    .concat(),
-                    [list.clone(), list.clone(), list.clone(), list.clone(), list].concat(),
-                )
-            })
             .map(|(mut springs, list)| {
                 let mut cache = HashMap::new();
                 count_valid(&mut springs, &list, 0, &mut Some(&mut cache))