/*[clinic input]
preserve
[clinic start generated code]*/

PyDoc_STRVAR(pairwise_new__doc__,
"pairwise(iterable, /)\n"
"--\n"
"\n"
"Return an iterator of overlapping pairs taken from the input iterator.\n"
"\n"
"    s -> (s0,s1), (s1,s2), (s2, s3), ...");

static PyObject *
pairwise_new_impl(PyTypeObject *type, PyObject *iterable);

static PyObject *
pairwise_new(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *iterable;

    if ((type == &pairwise_type ||
         type->tp_init == pairwise_type.tp_init) &&
        !_PyArg_NoKeywords("pairwise", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("pairwise", PyTuple_GET_SIZE(args), 1, 1)) {
        goto exit;
    }
    iterable = PyTuple_GET_ITEM(args, 0);
    return_value = pairwise_new_impl(type, iterable);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_groupby__doc__,
"groupby(iterable, key=None)\n"
"--\n"
"\n"
"make an iterator that returns consecutive keys and groups from the iterable\n"
"\n"
"  iterable\n"
"    Elements to divide into groups according to the key function.\n"
"  key\n"
"    A function for computing the group category for each element.\n"
"    If the key function is not specified or is None, the element itself\n"
"    is used for grouping.");

static PyObject *
itertools_groupby_impl(PyTypeObject *type, PyObject *it, PyObject *keyfunc);

static PyObject *
itertools_groupby(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"iterable", "key", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "groupby", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 1;
    PyObject *it;
    PyObject *keyfunc = Py_None;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 1, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    it = fastargs[0];
    if (!noptargs) {
        goto skip_optional_pos;
    }
    keyfunc = fastargs[1];
skip_optional_pos:
    return_value = itertools_groupby_impl(type, it, keyfunc);

exit:
    return return_value;
}

static PyObject *
itertools__grouper_impl(PyTypeObject *type, PyObject *parent,
                        PyObject *tgtkey);

static PyObject *
itertools__grouper(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *parent;
    PyObject *tgtkey;

    if ((type == &_grouper_type ||
         type->tp_init == _grouper_type.tp_init) &&
        !_PyArg_NoKeywords("_grouper", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("_grouper", PyTuple_GET_SIZE(args), 2, 2)) {
        goto exit;
    }
    if (!PyObject_TypeCheck(PyTuple_GET_ITEM(args, 0), &groupby_type)) {
        _PyArg_BadArgument("_grouper", "argument 1", (&groupby_type)->tp_name, PyTuple_GET_ITEM(args, 0));
        goto exit;
    }
    parent = PyTuple_GET_ITEM(args, 0);
    tgtkey = PyTuple_GET_ITEM(args, 1);
    return_value = itertools__grouper_impl(type, parent, tgtkey);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_teedataobject__doc__,
"teedataobject(iterable, values, next, /)\n"
"--\n"
"\n"
"Data container common to multiple tee objects.");

static PyObject *
itertools_teedataobject_impl(PyTypeObject *type, PyObject *it,
                             PyObject *values, PyObject *next);

static PyObject *
itertools_teedataobject(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *it;
    PyObject *values;
    PyObject *next;

    if ((type == &teedataobject_type ||
         type->tp_init == teedataobject_type.tp_init) &&
        !_PyArg_NoKeywords("teedataobject", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("teedataobject", PyTuple_GET_SIZE(args), 3, 3)) {
        goto exit;
    }
    it = PyTuple_GET_ITEM(args, 0);
    if (!PyList_Check(PyTuple_GET_ITEM(args, 1))) {
        _PyArg_BadArgument("teedataobject", "argument 2", "list", PyTuple_GET_ITEM(args, 1));
        goto exit;
    }
    values = PyTuple_GET_ITEM(args, 1);
    next = PyTuple_GET_ITEM(args, 2);
    return_value = itertools_teedataobject_impl(type, it, values, next);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools__tee__doc__,
"_tee(iterable, /)\n"
"--\n"
"\n"
"Iterator wrapped to make it copyable.");

static PyObject *
itertools__tee_impl(PyTypeObject *type, PyObject *iterable);

static PyObject *
itertools__tee(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *iterable;

    if ((type == &tee_type ||
         type->tp_init == tee_type.tp_init) &&
        !_PyArg_NoKeywords("_tee", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("_tee", PyTuple_GET_SIZE(args), 1, 1)) {
        goto exit;
    }
    iterable = PyTuple_GET_ITEM(args, 0);
    return_value = itertools__tee_impl(type, iterable);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_tee__doc__,
"tee($module, iterable, n=2, /)\n"
"--\n"
"\n"
"Returns a tuple of n independent iterators.");

#define ITERTOOLS_TEE_METHODDEF    \
    {"tee", (PyCFunction)(void(*)(void))itertools_tee, METH_FASTCALL, itertools_tee__doc__},

static PyObject *
itertools_tee_impl(PyObject *module, PyObject *iterable, Py_ssize_t n);

static PyObject *
itertools_tee(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
{
    PyObject *return_value = NULL;
    PyObject *iterable;
    Py_ssize_t n = 2;

    if (!_PyArg_CheckPositional("tee", nargs, 1, 2)) {
        goto exit;
    }
    iterable = args[0];
    if (nargs < 2) {
        goto skip_optional;
    }
    {
        Py_ssize_t ival = -1;
        PyObject *iobj = _PyNumber_Index(args[1]);
        if (iobj != NULL) {
            ival = PyLong_AsSsize_t(iobj);
            Py_DECREF(iobj);
        }
        if (ival == -1 && PyErr_Occurred()) {
            goto exit;
        }
        n = ival;
    }
skip_optional:
    return_value = itertools_tee_impl(module, iterable, n);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_cycle__doc__,
"cycle(iterable, /)\n"
"--\n"
"\n"
"Return elements from the iterable until it is exhausted. Then repeat the sequence indefinitely.");

static PyObject *
itertools_cycle_impl(PyTypeObject *type, PyObject *iterable);

static PyObject *
itertools_cycle(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *iterable;

    if ((type == &cycle_type ||
         type->tp_init == cycle_type.tp_init) &&
        !_PyArg_NoKeywords("cycle", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("cycle", PyTuple_GET_SIZE(args), 1, 1)) {
        goto exit;
    }
    iterable = PyTuple_GET_ITEM(args, 0);
    return_value = itertools_cycle_impl(type, iterable);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_dropwhile__doc__,
"dropwhile(predicate, iterable, /)\n"
"--\n"
"\n"
"Drop items from the iterable while predicate(item) is true.\n"
"\n"
"Afterwards, return every element until the iterable is exhausted.");

static PyObject *
itertools_dropwhile_impl(PyTypeObject *type, PyObject *func, PyObject *seq);

static PyObject *
itertools_dropwhile(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *func;
    PyObject *seq;

    if ((type == &dropwhile_type ||
         type->tp_init == dropwhile_type.tp_init) &&
        !_PyArg_NoKeywords("dropwhile", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("dropwhile", PyTuple_GET_SIZE(args), 2, 2)) {
        goto exit;
    }
    func = PyTuple_GET_ITEM(args, 0);
    seq = PyTuple_GET_ITEM(args, 1);
    return_value = itertools_dropwhile_impl(type, func, seq);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_takewhile__doc__,
"takewhile(predicate, iterable, /)\n"
"--\n"
"\n"
"Return successive entries from an iterable as long as the predicate evaluates to true for each entry.");

static PyObject *
itertools_takewhile_impl(PyTypeObject *type, PyObject *func, PyObject *seq);

static PyObject *
itertools_takewhile(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *func;
    PyObject *seq;

    if ((type == &takewhile_type ||
         type->tp_init == takewhile_type.tp_init) &&
        !_PyArg_NoKeywords("takewhile", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("takewhile", PyTuple_GET_SIZE(args), 2, 2)) {
        goto exit;
    }
    func = PyTuple_GET_ITEM(args, 0);
    seq = PyTuple_GET_ITEM(args, 1);
    return_value = itertools_takewhile_impl(type, func, seq);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_starmap__doc__,
"starmap(function, iterable, /)\n"
"--\n"
"\n"
"Return an iterator whose values are returned from the function evaluated with an argument tuple taken from the given sequence.");

static PyObject *
itertools_starmap_impl(PyTypeObject *type, PyObject *func, PyObject *seq);

static PyObject *
itertools_starmap(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *func;
    PyObject *seq;

    if ((type == &starmap_type ||
         type->tp_init == starmap_type.tp_init) &&
        !_PyArg_NoKeywords("starmap", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("starmap", PyTuple_GET_SIZE(args), 2, 2)) {
        goto exit;
    }
    func = PyTuple_GET_ITEM(args, 0);
    seq = PyTuple_GET_ITEM(args, 1);
    return_value = itertools_starmap_impl(type, func, seq);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_chain_from_iterable__doc__,
"from_iterable($type, iterable, /)\n"
"--\n"
"\n"
"Alternative chain() constructor taking a single iterable argument that evaluates lazily.");

#define ITERTOOLS_CHAIN_FROM_ITERABLE_METHODDEF    \
    {"from_iterable", (PyCFunction)itertools_chain_from_iterable, METH_O|METH_CLASS, itertools_chain_from_iterable__doc__},

PyDoc_STRVAR(itertools_combinations__doc__,
"combinations(iterable, r)\n"
"--\n"
"\n"
"Return successive r-length combinations of elements in the iterable.\n"
"\n"
"combinations(range(4), 3) --> (0,1,2), (0,1,3), (0,2,3), (1,2,3)");

static PyObject *
itertools_combinations_impl(PyTypeObject *type, PyObject *iterable,
                            Py_ssize_t r);

static PyObject *
itertools_combinations(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"iterable", "r", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "combinations", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    PyObject *iterable;
    Py_ssize_t r;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 2, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    iterable = fastargs[0];
    {
        Py_ssize_t ival = -1;
        PyObject *iobj = _PyNumber_Index(fastargs[1]);
        if (iobj != NULL) {
            ival = PyLong_AsSsize_t(iobj);
            Py_DECREF(iobj);
        }
        if (ival == -1 && PyErr_Occurred()) {
            goto exit;
        }
        r = ival;
    }
    return_value = itertools_combinations_impl(type, iterable, r);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_combinations_with_replacement__doc__,
"combinations_with_replacement(iterable, r)\n"
"--\n"
"\n"
"Return successive r-length combinations of elements in the iterable allowing individual elements to have successive repeats.\n"
"\n"
"combinations_with_replacement(\'ABC\', 2) --> AA AB AC BB BC CC\"");

static PyObject *
itertools_combinations_with_replacement_impl(PyTypeObject *type,
                                             PyObject *iterable,
                                             Py_ssize_t r);

static PyObject *
itertools_combinations_with_replacement(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"iterable", "r", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "combinations_with_replacement", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    PyObject *iterable;
    Py_ssize_t r;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 2, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    iterable = fastargs[0];
    {
        Py_ssize_t ival = -1;
        PyObject *iobj = _PyNumber_Index(fastargs[1]);
        if (iobj != NULL) {
            ival = PyLong_AsSsize_t(iobj);
            Py_DECREF(iobj);
        }
        if (ival == -1 && PyErr_Occurred()) {
            goto exit;
        }
        r = ival;
    }
    return_value = itertools_combinations_with_replacement_impl(type, iterable, r);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_permutations__doc__,
"permutations(iterable, r=None)\n"
"--\n"
"\n"
"Return successive r-length permutations of elements in the iterable.\n"
"\n"
"permutations(range(3), 2) --> (0,1), (0,2), (1,0), (1,2), (2,0), (2,1)");

static PyObject *
itertools_permutations_impl(PyTypeObject *type, PyObject *iterable,
                            PyObject *robj);

static PyObject *
itertools_permutations(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"iterable", "r", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "permutations", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 1;
    PyObject *iterable;
    PyObject *robj = Py_None;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 1, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    iterable = fastargs[0];
    if (!noptargs) {
        goto skip_optional_pos;
    }
    robj = fastargs[1];
skip_optional_pos:
    return_value = itertools_permutations_impl(type, iterable, robj);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_accumulate__doc__,
"accumulate(iterable, func=None, *, initial=None)\n"
"--\n"
"\n"
"Return series of accumulated sums (or other binary function results).");

static PyObject *
itertools_accumulate_impl(PyTypeObject *type, PyObject *iterable,
                          PyObject *binop, PyObject *initial);

static PyObject *
itertools_accumulate(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"iterable", "func", "initial", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "accumulate", 0};
    PyObject *argsbuf[3];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 1;
    PyObject *iterable;
    PyObject *binop = Py_None;
    PyObject *initial = Py_None;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 1, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    iterable = fastargs[0];
    if (!noptargs) {
        goto skip_optional_pos;
    }
    if (fastargs[1]) {
        binop = fastargs[1];
        if (!--noptargs) {
            goto skip_optional_pos;
        }
    }
skip_optional_pos:
    if (!noptargs) {
        goto skip_optional_kwonly;
    }
    initial = fastargs[2];
skip_optional_kwonly:
    return_value = itertools_accumulate_impl(type, iterable, binop, initial);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_compress__doc__,
"compress(data, selectors)\n"
"--\n"
"\n"
"Return data elements corresponding to true selector elements.\n"
"\n"
"Forms a shorter iterator from selected data elements using the selectors to\n"
"choose the data elements.");

static PyObject *
itertools_compress_impl(PyTypeObject *type, PyObject *seq1, PyObject *seq2);

static PyObject *
itertools_compress(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"data", "selectors", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "compress", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    PyObject *seq1;
    PyObject *seq2;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 2, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    seq1 = fastargs[0];
    seq2 = fastargs[1];
    return_value = itertools_compress_impl(type, seq1, seq2);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_filterfalse__doc__,
"filterfalse(function, iterable, /)\n"
"--\n"
"\n"
"Return those items of iterable for which function(item) is false.\n"
"\n"
"If function is None, return the items that are false.");

static PyObject *
itertools_filterfalse_impl(PyTypeObject *type, PyObject *func, PyObject *seq);

static PyObject *
itertools_filterfalse(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    PyObject *func;
    PyObject *seq;

    if ((type == &filterfalse_type ||
         type->tp_init == filterfalse_type.tp_init) &&
        !_PyArg_NoKeywords("filterfalse", kwargs)) {
        goto exit;
    }
    if (!_PyArg_CheckPositional("filterfalse", PyTuple_GET_SIZE(args), 2, 2)) {
        goto exit;
    }
    func = PyTuple_GET_ITEM(args, 0);
    seq = PyTuple_GET_ITEM(args, 1);
    return_value = itertools_filterfalse_impl(type, func, seq);

exit:
    return return_value;
}

PyDoc_STRVAR(itertools_count__doc__,
"count(start=0, step=1)\n"
"--\n"
"\n"
"Return a count object whose .__next__() method returns consecutive values.\n"
"\n"
"Equivalent to:\n"
"    def count(firstval=0, step=1):\n"
"        x = firstval\n"
"        while 1:\n"
"            yield x\n"
"            x += step");

static PyObject *
itertools_count_impl(PyTypeObject *type, PyObject *long_cnt,
                     PyObject *long_step);

static PyObject *
itertools_count(PyTypeObject *type, PyObject *args, PyObject *kwargs)
{
    PyObject *return_value = NULL;
    static const char * const _keywords[] = {"start", "step", NULL};
    static _PyArg_Parser _parser = {NULL, _keywords, "count", 0};
    PyObject *argsbuf[2];
    PyObject * const *fastargs;
    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
    Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 0;
    PyObject *long_cnt = NULL;
    PyObject *long_step = NULL;

    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 0, 2, 0, argsbuf);
    if (!fastargs) {
        goto exit;
    }
    if (!noptargs) {
        goto skip_optional_pos;
    }
    if (fastargs[0]) {
        long_cnt = fastargs[0];
        if (!--noptargs) {
            goto skip_optional_pos;
        }
    }
    long_step = fastargs[1];
skip_optional_pos:
    return_value = itertools_count_impl(type, long_cnt, long_step);

exit:
    return return_value;
}
/*[clinic end generated code: output=5364de2e143609b9 input=a9049054013a1b77]*/