From c54b92ebc99f65d914f9b331843dfc788103b5d7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Anders=20Ytterstr=C3=B6m?= <yttan@fastmail.se>
Date: Tue, 14 Dec 2021 07:03:44 +0100
Subject: [PATCH] Solve 2021:14 "Extended Polymerization" part 1

Solves 10 fine, but is sigkilled when running 40. refactoring needed.
---
 2021-python/solutions/day_14.py  | 48 ++++++++++++++++++++++++++++
 2021-python/tests/test_day_14.py | 54 ++++++++++++++++++++++++++++++++
 2 files changed, 102 insertions(+)
 create mode 100644 2021-python/solutions/day_14.py
 create mode 100644 2021-python/tests/test_day_14.py

diff --git a/2021-python/solutions/day_14.py b/2021-python/solutions/day_14.py
new file mode 100644
index 0000000..6422d99
--- /dev/null
+++ b/2021-python/solutions/day_14.py
@@ -0,0 +1,48 @@
+from solutions import BaseSolution
+from collections import Counter
+
+
+class Solution(BaseSolution):
+    input_file = "14.txt"
+
+    def __str__(self):
+        return "Day 14: Extended Polymerization"
+
+    def parse_input(self, data):
+        p, tv = data.strip().split("\n\n")
+        return p, [tuple(r.strip().split(" -> ")) for r in tv.splitlines()]
+
+    def solve(self, puzzle_input):
+        return self._solve(puzzle_input, 10)
+
+    def solve_again(self, puzzle_input):
+        return self._solve(puzzle_input, 40)
+
+    def _solve(self, puzzle_input, steps=10):
+        polymer, pir = puzzle_input
+        pir = dict(pir)
+        for _ in range(steps):
+            p = []
+            for i in range(len(polymer) - 1):
+                a, b = polymer[i : i + 2]
+                p.append(a)
+                s = pir.get(a + b)
+                if s:
+                    p.append(s)
+            p.append(polymer[-1])
+            polymer = p
+        c = [v for k, v in Counter(polymer).most_common()]
+        return max(c) - min(c)
+
+
+if __name__ == "__main__":
+    solution = Solution()
+    solution.show_results()
+
+"""
+Template:     NNCB
+After step 1: NCNBCHB
+After step 2: NBCCNBBBCBHCB
+After step 3: NBBBCNCCNBBNBNBBCHBHHBCHB
+After step 4: NBBNBNBBCCNBCNCCNBBNBBNBBBNBBNBBCBHCBHHNHCBBCBHCB
+"""
diff --git a/2021-python/tests/test_day_14.py b/2021-python/tests/test_day_14.py
new file mode 100644
index 0000000..3818f4d
--- /dev/null
+++ b/2021-python/tests/test_day_14.py
@@ -0,0 +1,54 @@
+import unittest
+
+from solutions.day_14 import Solution
+
+
+class Day14TestCase(unittest.TestCase):
+    def setUp(self):
+        self.solution = Solution()
+        self.puzzle_input = self.solution.parse_input(
+            """
+        NNCB
+
+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
+
+        """
+        )
+
+    def test_parse_puzzle_input(self):
+        data = """
+        NNCB
+
+CH -> B
+HH -> N
+CB -> H
+        """
+        assert self.solution.parse_input(data) == (
+            "NNCB",
+            [("CH", "B"), ("HH", "N"), ("CB", "H")],
+        )
+
+    def test_solve_first_part(self):
+        assert self.solution.solve(self.puzzle_input) == 1749 - 161
+
+    # def test_solve_second_part(self):
+    #     assert self.solution.solve_again(self.puzzle_input) == True
+
+
+if __name__ == "__main__":
+    unittest.main()