25.4. Sudoku Example: Cell Objects

Cell and CellGroup are subclasses of SetOfNine, which provides a property free with the type Set<Integer>. For a Cell it represents the individual candidate set. For a CellGroup the set is the union of all candidate sets of its cells, or the set of digits that still need to be allocated.

You can write rules that detect the specific situations that permit the allocation of a value to a cell or the elimination of a value from some candidate set. For example, you can create a list of Cell objects with 81 Cell and 27 CellGroup objects. You can also combine the linkage provided by the Cell properties cellRow, cellCol, cellSqr and the CellGroup property cells.