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What does this all mean?   ==> Rows, columns and blocks can all be represented with the same data structure!   We will use the interface ICellSet to represent the set of cells corresponding to a particular row, column or block.    There is also the implication that each cell "knows" which specific row, column and block to which it belongs, so

(In the support class, the Sudoku grid is modeled by an array of Rows. The Row class contains an ArrayList of HashSets, one HashSet of Integers for each square from that row. The HashSet contains possible values for the square.

To find final solutions from a partial solution, one should look for a square with multiple possible values, generate the different partial solutions by specifying that the square contains one of the values (and impose the restrictions specified by the rules of Sudoku on the content of the other squares), and then recurse for each of these possible solutions until no square has more than one possible value. If square becomes empty, then it will not lead to a final solution. If all squares have exactly one value, then we have a final solution.

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Your assignment is to implement:

• the method findSolution in the PartialSolution class.
• at least 5 more tests (3 for findSolution, 1 for isDeadEnd, 1 for isFinal).

Extra credit

For extra credit, improve the implementation of setElement and/or findSolution as you see fit, in order to improve the performance of the algorithms by examining fewer PartialSolution's. The improvement will be quantified by seeing if there is a decrease in the count of partial solutions in order to solve a puzzle (the count of partial solutions is returned by the getIntermediateSolutions() function of the PartialSolution class ).

Extra credit

Incorporate the supplied GeneratePuzzle utility capability into the main Sudoku solve, both in the view and the model, to enable the user to generate and solve any of the 50,000 supplied puzzles. Restriction: Keep using the setElement method in findSolution and do not change the contract of the setElement or findSolution methods.

Submission

Submit via Owlspace a .zip file containing all the files from the support code including those that you modified. Don't forget to add as header to the PartialSolution GameModel class, your names and ids.