![]() ![]() However, while you might suppose you have to wait for the next edition of your newspaper before you can have another sudoku fix, there is a growing range of apps available for iOS and Android that can fill the void. Solving a nine-by-nine sudoku square is a deeply satisfying - and often challenging - experience, and it’s for this reason sudoku has proven so popular over the past few years. You can practice this strategy by installing the SudokuCoach application on your Android™ device.Sudoku is arguably one of the best ways to spend a cold, rainy night at home by yourself. Hence there also exists a Strong Link between the two candidates of a "Bi-Value" Cell.Ī Weak Link as a link going from a Cell/group of Cells where the candidate is " ON" to a Cell/group of Cells where it is " OFF". If we consider a Bi-Value Cell, asserting that one of its candidates is not the solution implies that the other candidate must be the solution. To a Cell or a group of Cells where it then must be the solution (we say the candidate is in the " ON" state). Where we assert the candidate is not the solution (we say the candidate is in the " OFF" state) However, in the Chaining Strategies, we consider Strong Links as links going from a Cell or a group of Cells That contain a particular candidate: if the candidate is not the solution for the first Cell, then it must be the solution for the second Cell, and vice-versa. NB: more formally, a Strong Link is the relationship that exists between two Cells in a region (Row, Column or Square) when these two Cells are the only Cells in that region One of the two latters is the solution for its cell which eliminates candidate 5 in B1. In this example candidate 5 in B1 sees a blue candidate 5 in B6 and a pink candidate 5 in H1. Sees two candidates of different colors is eliminated by one of them (we do not know yet by which one). SIMPLE COLORING (SEES TWO DIFFERENT COLORS) : as one color must be the solution, a candidate that If the yellow state is not the solution, then the green state is the solution. Hence no candidates colored in yellow can be the solution in their respective cells. If cells in yellow identified the solution then candidate 2 would be the solution in two cells of Row "D", which is not possible. In this example candidate 2 has twice the yellow color in Row "D". SIMPLE COLORING (TWICE IN A UNIT) : if two Nodes in the Chain belong to the same region (Row, Column or Square) and if they have the same color, then this color can not be the solution because a candidate can not be the solution for two cells in the same region all candidates with this color can be eliminated. Because there are only two possible states for a candidate, all candidates with the same color must simultaneously be the solution or can not be the solution. This strategy analyzes such chains and uses colors to display these states (hence its name). If we consider a longer Chain exclusively made of Strong Links, the successive Nodes alternate from one state to the other. ![]() This, in turn and for the same reason, implies that the candidate can not be the solution for the third Cell in the Chain.Ĭonversely if we assume that the candidate in the Cell at one end of the Chain is the solution for that Cell, then it can not be the solution for the middle Cell and it must be the solution in the other end Cell of the Chain. ![]() If we assume that the candidate in the Cell at one end of the Chain is not the solution for that Cell, then it must be the solution for the next Cell in the Chain because of the definition of a Strong Link. If two Strong Links (also see note at the bottom of this page) share a common Cell, we can form a Chain of three Cells with the common Cell in the middle. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |