Finishing a Line

Level: Basic

Once a line satisfies all its clues, fill the remaining cells with X.

Once you have placed all the blocks a line's clues require, every remaining cell in that line is empty. Mark these cells with an X to finish it off.

In particular, a line whose clue is 0 (an empty line) can be blocked off with X from the very start. When the number of filled cells equals the clue sum, that line is complete.

Cleaning up a completed line with X passes new empty-cell information to the columns and rows that cross it, so the next confirmations appear in a chain.

Related techniques