Jelly-Fish extends Swordfish one further row and column. We are looking for either
1: four rows such that, in total, four cells are occupied in the row by a candidate number; or 2: four columns such that, in total, four cells are occupied in the column by a candidate number If this configuration is found then we can look in the opposite direction (if by row then down the column, if by column then across the row. If any candidates are found they can be eliminated. After the elimination both conditions above will hold.
How does it work? Pick any yellow cell in the example above that contains a 4. Keeping an eye on it. Pretend the solution actually is a 4. All others 4s in the row and columns are repressed. What we're left with is a Sword-Fish. The Sword-Fish logic then applies. Pick any 4 in the Sword-Fish and it reduces to an X-Wing. Since any combination of 4s on the grid are possible there is no room for 4s outside the grid - that align on the grid rows and columns.
No comments:
Post a Comment