Slow part 1 for day 14

inputs/day14.txt

@@ -0,0 +1,102 @@
+KOKHCCHNKKFHBKVVHNPN
+
+BN -> C
+OS -> K
+BK -> C
+KO -> V
+HF -> K
+PS -> B
+OK -> C
+OC -> B
+FH -> K
+NV -> F
+HO -> H
+KK -> H
+CV -> P
+SC -> C
+FK -> N
+VV -> F
+FN -> F
+KP -> O
+SB -> O
+KF -> B
+CH -> K
+VF -> K
+BH -> H
+KV -> F
+CO -> N
+PK -> N
+NH -> P
+NN -> C
+PP -> H
+SH -> N
+VO -> O
+NC -> F
+BC -> B
+HC -> H
+FS -> C
+PN -> F
+CK -> K
+CN -> V
+HS -> S
+CB -> N
+OF -> B
+OV -> K
+SK -> S
+HP -> C
+SN -> P
+SP -> B
+BP -> C
+VP -> C
+BS -> K
+FV -> F
+PH -> P
+FF -> P
+VK -> F
+BV -> S
+VB -> S
+BF -> O
+BB -> H
+OB -> B
+VS -> P
+KB -> P
+SF -> N
+PF -> S
+HH -> P
+KN -> K
+PC -> B
+NB -> O
+VC -> P
+PV -> H
+KH -> O
+OP -> O
+NF -> K
+HN -> P
+FC -> H
+PO -> B
+OH -> C
+ON -> N
+VN -> B
+VH -> F
+FO -> B
+FP -> B
+BO -> H
+CC -> P
+CS -> K
+NO -> V
+CF -> N
+PB -> H
+KS -> P
+HK -> S
+HB -> K
+HV -> O
+SV -> H
+CP -> S
+NP -> N
+FB -> B
+KC -> V
+NS -> P
+OO -> V
+SO -> O
+NK -> K
+SS -> H

inputs/sample.txt

@@ -1,21 +1,18 @@
-6,10
-0,14
-9,10
-0,3
-10,4
-4,11
-6,0
-6,12
-4,1
-0,13
-10,12
-3,4
-3,0
-8,4
-1,10
-2,14
-8,10
-9,0
+NNCB
 
-fold along y=7
-fold along x=5
+CH -> B
+HH -> N
+CB -> H
+NH -> C
+HB -> C
+HC -> B
+HN -> C
+NN -> C
+BH -> H
+NC -> B
+NB -> B
+BN -> B
+BB -> N
+BC -> B
+CC -> N
+CN -> C

src/bin/day14.rs

@@ -0,0 +1,63 @@
+use std::collections::HashMap;
+use std::error::Error;
+use std::fs::File;
+use std::io::{self, BufRead};
+use std::vec::Vec;
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let file = File::open("inputs/day14.txt")?;
+    let mut lines = io::BufReader::new(file).lines();
+
+    let mut polymer_template: Vec<char> = lines.next().unwrap().unwrap().chars().collect();
+    lines.next();
+
+    let mut rules: HashMap<(char, char), char> = HashMap::new();
+    while let Some(Ok(line)) = lines.next() {
+        if line == "" {
+            break;
+        }
+
+        let mut parts = line.split(" -> ");
+        let pair = parts.next().unwrap();
+        let new = parts.next().unwrap();
+
+        rules.insert(
+            (pair.chars().nth(0).unwrap(), pair.chars().nth(1).unwrap()),
+            new.chars().nth(0).unwrap(),
+        );
+    }
+
+    for i in 0..40 {
+        let mut next_step: Vec<char> = Vec::new();
+        next_step.push(polymer_template[0]);
+        for pair in polymer_template.windows(2) {
+            //next_step.push(pair[0]);
+            if rules.contains_key(&(pair[0], pair[1])) {
+                next_step.push(rules[&(pair[0], pair[1])]);
+            }
+            next_step.push(pair[1]);
+        }
+
+        polymer_template = next_step;
+
+        println!("{} : {}", i, polymer_template.len());
+    }
+
+    let mut dist: HashMap<char, usize> = HashMap::new();
+    for c in polymer_template.iter() {
+        let count = dist.get(c).unwrap_or_else(|| &0).clone();
+        dist.insert(*c, count + 1);
+    }
+
+    let mut counts: Vec<&usize> = dist.values().collect();
+    counts.sort();
+
+    println!(
+        "Answer1: {}",
+        *counts.last().unwrap() - *counts.first().unwrap()
+    );
+
+    println!("Answer2: {}", 0);
+
+    Ok(())
+}