Normal sudoku rules apply. Blue lines are “region sum lines”: Along a line, each line segment within a different 3x3 box must sum to the same total. Different lines may have different totals for their line segments.
Normal sudoku rules apply. Blue lines are “region sum lines”: Along a line, each line segment within a different 3x3 box must sum to the same total. Different lines may have different totals for their line segments.