TheAlgorithms-Python

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def hamming_distance(string1: str, string2: str) -> int:
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    """Calculate the Hamming distance between two equal length strings
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    In information theory, the Hamming distance between two strings of equal
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    length is the number of positions at which the corresponding symbols are
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    different. https://en.wikipedia.org/wiki/Hamming_distance
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    Args:
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        string1 (str): Sequence 1
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        string2 (str): Sequence 2
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    Returns:
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        int: Hamming distance
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    >>> hamming_distance("python", "python")
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    0
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    >>> hamming_distance("karolin", "kathrin")
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    3
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    >>> hamming_distance("00000", "11111")
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    5
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    >>> hamming_distance("karolin", "kath")
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    Traceback (most recent call last):
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      ...
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    ValueError: String lengths must match!
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    """
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    if len(string1) != len(string2):
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        raise ValueError("String lengths must match!")
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    count = 0
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    for char1, char2 in zip(string1, string2):
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        if char1 != char2:
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            count += 1
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    return count
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if __name__ == "__main__":
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    import doctest
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    doctest.testmod()
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