20 lines
508 B
Python
Executable File
20 lines
508 B
Python
Executable File
#!/usr/bin/env python3
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from string import ascii_lowercase, ascii_uppercase
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import fileinput
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import re
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def main():
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removals = set(map(''.join, zip(ascii_lowercase, ascii_uppercase)))
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removals = removals.union({r[::-1] for r in removals})
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remove_regex = re.compile('({})'.format('|'.join(removals)))
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line = next(fileinput.input()).strip()
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count = 1
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while count > 0:
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line, count = remove_regex.subn('', line)
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return len(line)
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if __name__ == '__main__':
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print(main())
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