TheAlgorithms-Python

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def multiplicative_persistence(num: int) -> int:
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    """
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    Return the persistence of a given number.
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    https://en.wikipedia.org/wiki/Persistence_of_a_number
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    >>> multiplicative_persistence(217)
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    2
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    >>> multiplicative_persistence(-1)
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    Traceback (most recent call last):
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        ...
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    ValueError: multiplicative_persistence() does not accept negative values
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    >>> multiplicative_persistence("long number")
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    Traceback (most recent call last):
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        ...
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    ValueError: multiplicative_persistence() only accepts integral values
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    """
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    if not isinstance(num, int):
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        raise ValueError("multiplicative_persistence() only accepts integral values")
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    if num < 0:
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        raise ValueError("multiplicative_persistence() does not accept negative values")
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    steps = 0
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    num_string = str(num)
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    while len(num_string) != 1:
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        numbers = [int(i) for i in num_string]
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        total = 1
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        for i in range(len(numbers)):
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            total *= numbers[i]
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        num_string = str(total)
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        steps += 1
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    return steps
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def additive_persistence(num: int) -> int:
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    """
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    Return the persistence of a given number.
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    https://en.wikipedia.org/wiki/Persistence_of_a_number
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    >>> additive_persistence(199)
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    3
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    >>> additive_persistence(-1)
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    Traceback (most recent call last):
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        ...
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    ValueError: additive_persistence() does not accept negative values
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    >>> additive_persistence("long number")
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    Traceback (most recent call last):
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        ...
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    ValueError: additive_persistence() only accepts integral values
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    """
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    if not isinstance(num, int):
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        raise ValueError("additive_persistence() only accepts integral values")
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    if num < 0:
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        raise ValueError("additive_persistence() does not accept negative values")
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    steps = 0
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    num_string = str(num)
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    while len(num_string) != 1:
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        numbers = [int(i) for i in num_string]
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        total = 0
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        for i in range(len(numbers)):
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            total += numbers[i]
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        num_string = str(total)
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        steps += 1
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    return steps
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if __name__ == "__main__":
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    import doctest
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    doctest.testmod()
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