Intermediate

Claiming

A row or column confines a candidate to one box.

Explanation

If all possible cells for a digit in a row or column fall inside one box, that box must host the digit on that line. Remove it from the other cells of the box.

Claiming example Sudoku board 5 3 7 6 1 9 5 9 8 6 8 6 3 4 8 3 1 7 2 6 6 2 8 4 1 9 5 8 7 9
An example board where Claiming applies

Practice tip

Scan each row and column digit by digit, watching for candidates bunched in one box.

Example steps

  1. Find a row or column where one candidate only appears inside a single box.
  2. That box must host the digit on this line.
  3. Remove the candidate from the other cells of that box.

Try this technique on a real puzzle.

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