44 lines
984 B
Python
44 lines
984 B
Python
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from collections import Counter
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class Polymer:
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def __init__(self, data, remove=None):
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self.units = list(filter(lambda u: u.lower() != remove, data))
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self.index = 0
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def __len__(self):
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return len(self.units)
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def test(self, i):
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try:
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a, b = self.units[i], self.units[i + 1]
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except IndexError:
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return False
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if a != b and a.lower() == b.lower():
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return True
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return False
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def react(self):
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while self.test(self.index):
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del self.units[self.index:self.index + 2]
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if self.index > 0:
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self.index -= 1
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def process(self):
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while self.index < len(self) - 1:
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self.react()
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self.index += 1
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with open('data/05.txt') as f:
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data = f.read().strip()
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results = []
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for unit_type in set(data.lower()):
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p = Polymer(data, remove=unit_type)
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p.process()
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results.append(len(p))
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print(min(results))
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