Pointing Pairs

Nasıl Çalışır

When all candidates for a particular number within a 3x3 box are confined to a single row or column, that number can be eliminated from other cells in that row or column outside the box.

Adım Adım

1. Within a 3x3 box, find a candidate number that only appears in one row (or column).
2. Since it must go in that row within the box, eliminate it from the same row outside the box.