Two sets of N cells with N+1 candidates each, linked by a Restricted Common Candidate; their other common candidate is eliminated from all cells seeing both ALS.
An ALS is N cells with N+1 candidates. Two ALSs are linked by a Restricted Common Candidate (RCC) — a digit that can only go in one of the two ALSs. This means any other candidate shared by both ALSs can be eliminated from cells seeing both.
Extremely powerful; generalizes Naked Pairs, XY-Wings, and many other techniques.
346 | 256 | 8 | 35 | 14 | 9 | 1257 | 24 | 67 |
| 1 | 259 | 349 | 35 | 6 | 7 | 59 | 248 | 89 |
456 | 7 | 4569 | 2 | 14 | 8 | 159 | 3 | 69 |
25 | 59 | 1 | 8 | 7 | 3 | 29 | 6 | 4 |
347 | 8 | 34 | 6 | 9 | 2 | 37 | 1 | 5 |
2367 | 69 | 369 | 1 | 5 | 4 | 2379 | 28 | 789 |
56 | 3 | 56 | 7 | 8 | 1 | 4 | 9 | 2 |
| 8 | 4 | 2 | 9 | 3 | 5 | 6 | 7 | 1 |
| 9 | 1 | 7 | 4 | 2 | 6 | 8 | 5 | 3 |
This 9×9 puzzle is solver-verified to require this technique on its solution path.