cython

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# mode: run
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from libc.stdlib cimport abs as c_int_abs, qsort as libc_qsort
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def libc_int_abs(int x):
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    """
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    >>> libc_int_abs(5)
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    5
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    >>> libc_int_abs(-5)
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    5
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    """
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    return c_int_abs(x)
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cdef int gt(const void* v1, const void* v2) noexcept nogil:
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    return ((<int*>v1)[0] - (<int*>v2)[0])
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cdef int lt(const void* v1, const void* v2) noexcept nogil:
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    return - gt(v1, v2)
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def qsort(values, direction='lt'):
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    """
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    >>> data = [1, 9, 3, 2, 5]
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    >>> qsort(data, 'gt')
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    [1, 2, 3, 5, 9]
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    >>> qsort(data, 'lt')
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    [9, 5, 3, 2, 1]
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    """
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    cdef int[5] carray = values[:5]
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    libc_qsort(carray, 5, sizeof(int), lt if direction == 'lt' else gt)
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    return carray
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