39 lines
984 B
Python
Executable file
39 lines
984 B
Python
Executable file
#!/usr/bin/env python
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import sys
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def solve(input: str) -> int:
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def reduce_polymer(polymer: str) -> str:
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for i in range(26):
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lower, upper = chr(ord("a") + i), chr(ord("A") + i)
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polymer = polymer.replace(lower + upper, "")
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polymer = polymer.replace(upper + lower, "")
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return polymer
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def fully_reduced(polymer: str) -> str:
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while True:
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reduced = reduce_polymer(polymer)
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if reduced == polymer:
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return polymer
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polymer = reduced
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assert False # Sanity check
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def remove_defective(polymer: str, unit: str) -> str:
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return polymer.replace(unit.lower(), "").replace(unit.upper(), "")
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polymer = input.strip()
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return min(
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len(fully_reduced(remove_defective(polymer, chr(ord("a") + i))))
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for i in range(26)
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)
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def main() -> None:
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input = sys.stdin.read()
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print(solve(input))
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if __name__ == "__main__":
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main()
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