cimport cython


cpdef select_by_sorting(list a, Py_ssize_t rank)


@cython.locals(i=Py_ssize_t, j=Py_ssize_t, n=Py_ssize_t)
cpdef selectk(Py_ssize_t k, list a, Py_ssize_t rank)


@cython.locals(a=Py_ssize_t, b=Py_ssize_t, i=Py_ssize_t, j=Py_ssize_t)
cpdef select(list xs, Py_ssize_t k)

cdef choose_pivot(list xs, Py_ssize_t a, Py_ssize_t b)

cdef median_of_three(x, y, z)


@cython.locals(i=Py_ssize_t, j=Py_ssize_t)
cpdef select2(list xs, Py_ssize_t a, Py_ssize_t b, Py_ssize_t k)

@cython.locals(third=Py_ssize_t)
cdef tuple choose_pivots(list xs, Py_ssize_t a, Py_ssize_t b)

@cython.locals(i=Py_ssize_t, j=Py_ssize_t, k=Py_ssize_t)
cdef tuple partition3(list xs, Py_ssize_t a, Py_ssize_t b, x, y)