Logic Masters Deutschland e.V.

Normal Sudoku rules apply (each row, column, and given 3x3 box must contain the digits 1 to 9). Everything is mod 10. So a 6 might mean 6, or 16, or 26, etc.

The following variants are all subject to the mod 10 rule. Digits in a cage must add to the sum in the top left corner - e.g. if the number in the corner is 0, the digits might sum to 10, 20, 30, etc. Digits along an arrow must sum to the number in the circle - e.g. if a 4 is in the circle, the digits along the arrow might sum to 4, 14, 24, etc. The blue lines are region sum lines. For each line, digits on the line have an equal sum N within each box it passes through. If a line passes through the same box more than once, each individual segment of such a line within that box sums to N separately. So if one segment sums to 16, the other segments might sum to 6, 16, 26, etc. N can be different for different lines.

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