Hi! Welcome to my first kata.

In this kata the task is to take a list of integers (positive and negative) and split them according to a simple rule; those ints greater than or equal to the key, and those ints less than the key (the itself key will always be positive).

However, in this kata the goal is to sort the numbers IN PLACE, so DON'T go messing around with the order in with the numbers appear.

You are to return a nested list. If the list is empty, simply return an empty list.

Confused? Okay, let me walk you through an example...

    The input is: [1, 1, 1, 0, 0, 6, 10, 5, 10], the key is: 6
Okay so the first five numbers are less than the key, 6, so we group them together.

    [1, 1, 1, 0, 0]
The next two numbers, 6 & 10, are both >= 6 to they belong in a seperate group, which we will add to the first group. Like so:

    [[1, 1, 1, 0, 0], [6, 10]]
The next two numbers are 5 & 10. Since the key is 6 these two numbers form seperate groups, which we will add to the previous result. like so:

    [[1, 1, 1, 0, 0], [6, 10], [5], [10]]
And voila! We're done.
 
Here are a few more basic examples:

    group_ints([1, 0], key= 0)  
    --> [[1,0]]
  
    group_ints([1, 0, -1, 5], key= 0) 
    --> [[1, 0], [-1], [5]]
  
    group_ints([1, 0, -1, 5], key= 5) 
    --> [[1, 0, -1], [5]]

Good luck guys/gals!

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

def _disabled_input(*args, **kwargs):
    raise RuntimeError("input() is disabled in callable mode")
builtins.input = _disabled_input

ns = {"__name__": "__judge__"}  # prevent if __name__ == "__main__" blocks
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = 'def group_ints(lst, key=0):\n    if not lst: return []\n    l, index = [[lst[0]]], 0\n    for x in lst[1:]:\n        if l[index][-1] < key and x < key:\n            l[index].append(x)\n        elif l[index][-1] >= key and x >= key:\n            l[index].append(x)\n        else:\n            l.append([x])\n            index += 1\n    return l'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'group_ints'
if _fn_name:
    if "Solution" in ns:
        try:
            _obj = ns["Solution"]()
            if hasattr(_obj, _fn_name):
                _target = getattr(_obj, _fn_name)
        except Exception:
            _target = None
    if _target is None and _fn_name in ns and callable(ns[_fn_name]):
        _target = ns[_fn_name]
# Fallback: if there's exactly one user-defined function, use it
if _target is None:
    _cands = [v for k, v in ns.items() if callable(v) and getattr(v, "__module__", "") in ("__judge__", "__main__")]
    _user_funcs = [c for c in _cands if getattr(c, "__name__", "").startswith("_") is False]
    if len(_user_funcs) == 1:
        _target = _user_funcs[0]
if _target is None:
    raise RuntimeError(f"Could not resolve callable '{_fn_name}'")

_raw = sys.stdin.read().strip()
if _raw:
    _parsed = json.loads(_raw)
    if isinstance(_parsed, dict):
        _kwargs = _parsed.get("kwargs", {})
        _args = _parsed.get("args", [])
    else:
        _args, _kwargs = _parsed, {}
else:
    _args, _kwargs = [], {}
if not isinstance(_args, (list, tuple)):
    _args = [_args]
_res = _target(*_args, **_kwargs)
try:
    sys.stdout.write(repr(_res) + "\n")
except Exception:
    pass

```

Measured memory_bytes: 5642