TheAlgorithms-Python

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"""
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Calculates the sum of two non-negative integers using bitwise operators
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Wikipedia explanation: https://en.wikipedia.org/wiki/Binary_number
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"""
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def bitwise_addition_recursive(number: int, other_number: int) -> int:
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    """
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    >>> bitwise_addition_recursive(4, 5)
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    9
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    >>> bitwise_addition_recursive(8, 9)
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    17
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    >>> bitwise_addition_recursive(0, 4)
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    4
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    >>> bitwise_addition_recursive(4.5, 9)
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    Traceback (most recent call last):
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        ...
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    TypeError: Both arguments MUST be integers!
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    >>> bitwise_addition_recursive('4', 9)
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    Traceback (most recent call last):
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        ...
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    TypeError: Both arguments MUST be integers!
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    >>> bitwise_addition_recursive('4.5', 9)
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    Traceback (most recent call last):
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        ...
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    TypeError: Both arguments MUST be integers!
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    >>> bitwise_addition_recursive(-1, 9)
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    Traceback (most recent call last):
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        ...
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    ValueError: Both arguments MUST be non-negative!
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    >>> bitwise_addition_recursive(1, -9)
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    Traceback (most recent call last):
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        ...
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    ValueError: Both arguments MUST be non-negative!
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    """
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    if not isinstance(number, int) or not isinstance(other_number, int):
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        raise TypeError("Both arguments MUST be integers!")
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    if number < 0 or other_number < 0:
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        raise ValueError("Both arguments MUST be non-negative!")
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    bitwise_sum = number ^ other_number
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    carry = number & other_number
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    if carry == 0:
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        return bitwise_sum
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    return bitwise_addition_recursive(bitwise_sum, carry << 1)
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if __name__ == "__main__":
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    import doctest
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    doctest.testmod()
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