1. I feel like “trial and error” is often not a great way to solve puzzles. If you can brute force your way to a solution, that’s usually a sign of poor puzzle design. To be clear, I’m not saying whether this one is easy to brute force, just saying if it is, that’s a different problem.

2. Even if brute force was a viable option for solving, an easy fix is to have a “submit” button when you think you’ve solved it (and that can track strikes for invalid submissions).