wow bit shifting so clever

me too, i had the same idea, but it still timed out

Mathematically, it the same, but sometimes, we lose sense with over-refactoring.

how did you derive this solution?

Good Kata :D and way harder than some 3kyu tasks
... or I really suck at bfs

thanks, it is approved

Here's a fork that fixes it

interesting kata, i was able to solve it quickly with brute force in python, don't know if that's intended.
Here is a great explaination how a more efficient algorithm works.
https://math.stackexchange.com/a/2804461/186763

When I first saw this, I was like what??!! :D

AMAZIIIIIINGGGGG

thanks!

one of the few solutions that optimize performance by stopping as soon as the element is found

Added the hint about the origin. Thanks for the suggestion!

Thanks for answering.
I missed this line from description:

Executing a toggle operation at coordinates (x, y) will toggle all switches in the row y and column x.

(y, x) is more often used as you iterate first on the rows rather than the columns in a 2D list (see how numpy handles shapes for example, or numpy.argwhere method returning indexes).

Anyway this line is already in description, my bad.

Nevertheless, in this case, can you also add where is the origin in order to be cristal clear please?