You are stacking some boxes containing gold weights on top of each other. If a box contains more weight than the box below it, it will crash downwards and combine their weights. e.g. If we stack [2] on top of [1], it will crash downwards and become a single box of weight [3]
```
[2]
[1] --> [3]
```
Given an array of arrays, return the bottom row (i.e. the last array) after all crashings are complete.
```
crashing_weights([[1, 2, 3],  --> [[1, 2,  ],      [[1,  ,  ]],
                  [2, 3, 1],  -->  [2, 3, 4],  -->  [2, 2,  ],
                  [3, 1, 2]])      [3, 1, 2]]  -->  [3, 4, 6]]

therefore return [3, 4, 6]
```

## More details

boxes can be stacked to any height, and the crashing effect can snowball:
```
[3]
[2]     [5]
[4] --> [4] --> [9]
```
Crashing should always start from as high up as possible -- this can alter the outcome! e.g.
```
[3]                      [3]
[2]     [5]              [2]     [3]
[1] --> [1] --> [6], not [1] --> [3] 
```
Weights will always be integers. The matrix (array of arrays) may have any height or width > 1, and may not be square, but it will always be "nice" (all rows will have the same number of columns, etc).

```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 = 'from functools import reduce\n\ndef crashing_weights(weights):\n    return reduce(crash_if_heavier, weights)\n\ndef crash_if_heavier(upper_row, lower_row):\n    return [wl if wu <= wl else wu + wl for wu, wl in zip(upper_row, lower_row)]'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'crashing_weights'
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: 5360