Detailed instructions for working a group puzzle of type 'Sudoku-12'
The 12 elements in each group of this type of puzzle are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, and B.
Every group in the puzzle must contain exactly this set of elements.
In a Sudoku-12 puzzle, each row is a group numbered as shown in the figure above.
In a Sudoku-12 puzzle, each column is a group numbered as shown in the figure above.
In a Sudoku-12 puzzle, each 4x3 rectangle is a group numbered as shown in the figure above.