Logic Masters Deutschland e.V.

Rules:

Draw a non-intersecting loop through the centers of all cells except clued cells and shaded cells. A given clue indicates the number of shaded cells in the direction of the arrow (yajilin), as well as the number of shaded cells in that clue’s region (heyawake). A “?” represents the same number for both yajilin and heyawake. The value of “?” may differ between regions.

Clued cells cannot be shaded. Shaded cells cannot be orthogonally adjacent to each other. Any contiguous orthogonal string of unshaded cells (including clued cells) cannot cross more than one region border.

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