Logic Masters Deutschland e.V.

This is a sandwich Sudoku where the role of the 1s and the 9s can be filled by any digit.

• Normal Sudoku rules apply.
• Clues outside the grid indicate the sum of two (crust) cells, which is the same as the sum of digits sandwiched between them. Clues on both sides means that there are two sandwiches in that row or column; side does not matter.
• A cell is either crust or not crust, both in its row and column. I.e. sandwiches can't overlap, but may share a crust cell.
• If a cell has been used as a crust cell for a clue, you cannot use another non-adjacent cell in the same row or column as crust to satisfy another clue.

The image to the right, of an incomplete puzzle, illustrates how the clues work. The solver has found placements of some digits that satisfies all but the 17 clue. In the last column, the potential crust cells are pink. The dark green cells are not allowed, since that would require another clue for the row.

F-puzzles

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