Logic Masters Deutschland e.V.

Normal sudoku rules apply Sum/Difference Lines: Each line connecting two circles is a so-called Sum/Difference Line. One of the circled digits indicates the sum of all values along the line. The other circled digit indicates the difference between the highest and the lowest value on the line. (Which circle indicates the sum and which the difference has to be determined by the solver. If a circle is bounding multiple lines, it may serve different purposes for those, i.e. it can indicate the sum for one line and the maximal difference of another one.) Doublers: There are nine Doubler cells in the grid, exactly one in each row, column and marked 3x3 box and filled with a complete set of the digits 1-9. The value of a Doubler cell is twice the digit in that cell.
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