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Validate the Board:
Clicking the {Validate }} Button button will pop up a message dialog box with information on the state of the board. This button, which is fully operational in the supplied code, is a very useful tool to check your code's performance as you work. The information shown includes
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All recution and solving operations should always leave the board in a valid state, unless the board is unsolvable, wherein a cell may become empty.
See the note about the GameModel.validateBoard() method in the Code Details wiki page!!
Perform a Single Reduction Pass on the Board.
When your reduceBoard() method is working, clicking the Reduce button will perform a single pass reduction on every cell on the board. You should thus be able to progress towards a solution by repeatedly clicking the Reduce button, though you might end up with either an unsolvable or irreducible board. Attempting to reduce an unsolvable or irreducible board will have no effect on the board.
Finding a Minimum Choice Cell
Solving the Board
Generating Solvable Puzzles
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