Bowman's Bingo
Extreme
Reference only
Last Resort: guess a candidate and manually trace forced Naked/Hidden Singles as far as they go — a contradiction eliminates the guess, same idea as Trial and Error but tracked by hand.
The solver does not attempt this technique, so Smart Hint will never suggest it. It is documented because you may still want to spot it yourself.
- Where the conclusion lands
How it works
- Guess A1 = 1, then follow only forced Singles from there (no other technique) as far as they'll go — no guessing again partway through.
- If that chain of forced Singles ever produces a duplicate digit in some row, column, or box — like both E1 and A5 needing to be 1 — the original guess was wrong. Eliminate it and try the alternative.
- Named "Bingo" for calling out each forced placement in turn, like a bingo caller — it's the historical precursor to modern Forcing Chains.