TheAlgorithms-Python

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def is_contains_unique_chars(input_str: str) -> bool:
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    """
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    Check if all characters in the string is unique or not.
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    >>> is_contains_unique_chars("I_love.py")
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    True
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    >>> is_contains_unique_chars("I don't love Python")
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    False
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    Time complexity: O(n)
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    Space complexity: O(1) 19320 bytes as we are having 144697 characters in unicode
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    """
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    # Each bit will represent each unicode character
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    # For example 65th bit representing 'A'
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    # https://stackoverflow.com/a/12811293
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    bitmap = 0
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    for ch in input_str:
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        ch_unicode = ord(ch)
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        ch_bit_index_on = pow(2, ch_unicode)
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        # If we already turned on bit for current character's unicode
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        if bitmap >> ch_unicode & 1 == 1:
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            return False
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        bitmap |= ch_bit_index_on
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    return True
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if __name__ == "__main__":
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    import doctest
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    doctest.testmod()
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