Logic Masters Deutschland e.V.

• Each row, column, and region must contain the digits 1-9 once each. Regions consist of a set of nine orthogonally connected cells and must be determined by the solver.
• All circles indicate the number of cells seen in all four orthogonal directions (including itself). Region borders block vision. Not all possible circles are given.
• Draw a single closed loop moving orthogonally through centers of some cells. The loop does not cross nor intersect itself. If it enters a region, it must visit every cell of the region before leaving it. Red circles are visited by the loop, black circles are not.
• The grid is partially covered with fog. Correctly placed digits will clear the fog around that cell.

Puzzle:

  Solve online (Sudoku Pad)

Hint: (highlight text below if you want to read it)

  How many cells will the finished loop occupy?..
  An even number, so there is an even number of regions on the loop...
  4 regions is not enough to connect the given segments.