39 lines
829 B
Python
39 lines
829 B
Python
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#!/usr/bin/env python3
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with open('input.txt', 'r') as f:
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polymer = f.read()
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print('Polymer length:', len(polymer))
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modifications = True
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rounds = 0
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while modifications:
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modifications = False
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rounds += 1
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mods = 0
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new_polymer = []
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skip = False
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for i, el in enumerate(polymer[:-1]):
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if skip:
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skip = False
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continue
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next_el = polymer[i + 1]
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if el != next_el and el.upper() == next_el.upper():
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modifications = True
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mods += 1
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skip = True
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continue
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new_polymer.append(el[-1])
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if not skip:
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new_polymer.append(polymer[-1])
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polymer = ''.join(new_polymer)
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print(f'Round: {rounds}. Modifications found: {mods}. Polymer length: {len(polymer)}')
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print(polymer)
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print(len(polymer))
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