******************************************************************************* Minesweeper Consistency Solver ******************************************************************************* The minesweeper consistency problem is stated as follows: Given a ROWSxCOLS minesweeper grid of some exposed tiles numbering the mines surrounding them, does there exist a valid placement of n mines? ******************************************************************************* TODO ******************************************************************************* 1. Order unknowns: Order unknowns by how constrained they are, and assign values to the most constrained ones first. This allows for more pruning at the top of the search tree. 2. Derive values: Once an UNKNOWN is assigned to ON or OFF, other unknowns may now only have one legal value. Force the assignment of that value. 3. Likely value: In case both ON and OFF are valid, attempt to judge what is the most likely value, and assign that one first.