Love that you used a bitwise operator. Super clever.

Definitely beside math approach, best brute force there, without modulo or repeating multiplication, grants. There is not many of them there :D

Fixed just now.

Change test.expect to Test.expect (with a capital "T") in the "Sample Tests" section.

Same problem here.

it seems that you modified the input array.

random test are broken.
Every time:"There should be 0 solutions in this list of words. - Expected: 0, instead got: 'my_answer'".
But [words] has sets of words like [call,cell,cill,coll,cull] and other.

Resolved. (it's necessary to fix random tests)
If i change incoming array words(at the end length = 0), then i get 'Expected: 0' and random test are incorrect.
I have to make a copy of an incoming array.

Hi,

I have a working solution for the given test samples although when I try to run any kind of code the error message will be always : "AttributeError: 'list' object has no attribute 'expect' ". Even when the function returns the parameter only, or just passes. There is one exception: in case of only 1 line "def find solution(words):" the message will be:

"File "", line 230
tests = [
^
IndentationError: expected an indented block"

I believe this has nothing to do with my code.

Thank you. :)

Nice!