Logic Masters Deutschland e.V.

Play online in Sudokupad.

Unsure of difficulty as I've gotten varying responses but 3 stars seems about right. It is possible to brute force this puzzles, however I encourage finding the intended path, which doesn't contain any extended case checking chains.

Rules

• Place digits 1-9 in every row, column, and box exactly once.


• Modular Double Arrows : Sum of the digits on an arrow equals the sum of the digits on its two circles. A set of three sequential digits along a modular arrow (including the circles) must contain a complete set of residues modulo 3, i.e. one digit from {1,4,7}, one from {2,5,8}, and one from {3,6,9}.


• An inequality sign separates two digits from different residue classes and points towards the smaller of the two digits.