[2021] day 14 python naive

2021/.input/day14

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

2021/Python/day14.py

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+import re
+
+
+input_pattern = re.compile(r"([A-Z]+) -> ([A-Z]+)")
+
+
+def load():
+    with open("../.input/day14", "r") as f:
+        start, rest = f.read().split("\n\n")
+    return start, input_pattern.findall(rest)
+
+
+def step(start, rules):
+    output = []
+    for pair in zip(start, start[1:]):
+        c1, c2 = pair
+        output.append(c1)
+        output.append(rules[c1+c2])
+    output.append(start[-1])
+    return output
+
+
+def solve1():
+    start, rules = load()
+    rules = {k: v for k, v in rules}
+
+    for _ in range(10):
+        start = step(start, rules)
+
+    chars = {}
+    for c in start:
+        chars[c] = chars.get(c, 0) + 1
+
+    values = list(sorted(chars.values(), reverse=True))
+    return values[0] - values[-1]
+
+
+if __name__ == "__main__":
+    print(solve1())
+