Day 14

Author: Widdin

2021/14/input.txt

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

2021/14/main.py

@@ -0,0 +1,81 @@
+from collections import defaultdict, Counter
+
+
+class Day14:
+
+    def __init__(self):
+        self.puzzle_input = self.get_puzzle_input()
+
+    def part_one(self) -> int:
+        return self.run_steps(steps=10)
+
+    def part_two(self) -> int:
+        return self.run_steps(steps=40)
+
+    def run_steps(self, steps):
+        data = self.get_puzzle_input().copy()
+
+        polymer_template = None
+        pair_insertion_rules = defaultdict(str)
+
+        for line in data:
+            if '->' in line:
+                pair_from, pair_to = line.split(' -> ')
+                pair_insertion_rules[pair_from] = pair_to
+            elif line != '':
+                polymer_template = list(line)
+
+        polymer_template_pairs = defaultdict(int)
+        for i in range(len(polymer_template) - 1):
+            a, b = polymer_template[i], polymer_template[i + 1]
+            polymer_template_pairs[a + b] += 1
+
+        for i in range(steps):
+            polymer_template_pairs = self.find_new_pairs(polymer_template_pairs, pair_insertion_rules)
+
+        letters = self.count_letters(polymer_template_pairs)
+        letters[polymer_template[-1]] += 1
+
+        c = Counter(letters)
+        most_letter, most_count = c.most_common()[0]
+        least_letter, least_count = c.most_common()[-1]
+
+        return most_count - least_count
+
+    @staticmethod
+    def count_letters(polymer_template_pairs):
+        letters = defaultdict(int)
+        for key, value in polymer_template_pairs.items():
+            first_letter = key[0]
+            letters[first_letter] += value
+
+        return letters
+
+    @staticmethod
+    def find_new_pairs(polymer_template, pair_insertion_rules):
+        new_polymer_template = defaultdict(int)
+
+        for key, value in polymer_template.items():
+
+            first_letter = key[0]
+            second_letter = key[1]
+
+            new_letter = pair_insertion_rules[key]
+
+            new_polymer_template[first_letter + new_letter] += value
+            new_polymer_template[new_letter + second_letter] += value
+
+        return new_polymer_template
+
+    @staticmethod
+    def get_puzzle_input() -> list:
+        lst = []
+        with open("input.txt") as file:
+            for line in file:
+                lst.append(line.rstrip())
+        return lst
+
+
+day = Day14()
+print(f'Result part 1: {day.part_one()}')
+print(f'Result part 2: {day.part_two()}')