The article talks about a 2-dimensional grid which starts at (0,0) (bottom right) and extends infinitely to the right and the top, so all (x,y) for non-negative integers x,y exist. But x or y negative does not exist. Given a list of possible jumps e.g. (+1,+10) or (-20,+13), and a target destination, e.g. (700,1). Does there exist a series of valid jumps that takes you from (0,0) to (700,1) without ever going off grid (i.e. into negative territory)?
This problem might or might not be NP-Harder. However, now extend the problem to higher dimensional grids. At some number of dimensions, the problem becomes definitely NP-Harder (i.e. NP-hard, decidable, but not in NP)
It works in pre-interview filtering rounds because companies hiring processes are usually broken and the smartest people are not working on those aspect.
If, on the actual job, you're copy-pasting buggy ChatGPT code, someone will notice. If the other people at the company don't notice and do something about it, the company isn't likely to survive for too long.
This problem might or might not be NP-Harder. However, now extend the problem to higher dimensional grids. At some number of dimensions, the problem becomes definitely NP-Harder (i.e. NP-hard, decidable, but not in NP)