3 ms·

It's a left-shortest matching back-tracker. Not to be used in practice. I'm sure this implementation features in various text books.

• maccard 4y ago
  So it's doable if you know the solution and have seen it before, but otherwise it's pretty damn difficult
  • samatman 4y ago
    The issue here is the pathological performance under crafted inputs, I don't believe GP was saying it's easy to write or uninteresting history.