Last edited by emanymton on December 08, 2007 • 8:10 am, edited 2 times in total.
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Dear Tex,
Sudoku is a game requiring the use of logic, reasoning, thinking and ‘trial and error’ to solve. The games are rated up to and including fiendish and insane (where a low number of squares are given).
Two questions:
1. Is it possible to solve challenging Sudoku games using only reason and logic (i.e. without guessing and 'trial and error)?
2. Is there a limit of ‘givens’ where the Sudoku game becomes unsolvable? I have worked out a ‘23 given’ Sudoku game.
Always yours,
Ema Nymton
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Dear Tex,
Sudoku is a game requiring the use of logic, reasoning, thinking and ‘trial and error’ to solve. The games are rated up to and including fiendish and insane (where a low number of squares are given).
Two questions:
1. Is it possible to solve challenging Sudoku games using only reason and logic (i.e. without guessing and 'trial and error)?
2. Is there a limit of ‘givens’ where the Sudoku game becomes unsolvable? I have worked out a ‘23 given’ Sudoku game.
Always yours,
Ema Nymton
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We Cheat The Other Guy And Pass The Savings On To You.
This depends on how the 'givens' are arranged and this is also what determines the difficulty level of a particular game. Games that are rated "Easy" can be solved with what is called the "scanning" technique. That is where you scan each empty square and look for squares that only allow one possibility. You can do this methodically, and complete an easy game this way.1. Is it possible to solve challenging Sudoku games using only reason and logic (i.e. without guessing and 'trial and error)?
Intermediate and hard games will require more analysis. At some point, you will only be able to reduce a square to either of two possibilities. Depending on the circumstances, there are other strategies that you will need and these may include picking one of the two possibilities (guessing.)
This also depends on how the givens are arranged. According to the Wikipedia entry, the fewest number of givens that render a unique solution is unknown. So far, the smallest number that has been found is 17. Also, it is possible to have as many as 77 (four short of a complete grid). But that is very dependent on the arrangement of the givens. So the answer is not simple.2. Is there a limit of ‘givens’ where the Sudoku game becomes unsolvable? I have worked out a ‘23 given’ Sudoku game.
I haven't played Sudoku in a while, but I think a truly hellish difficulty would be similar to the brick game at the Anasazi ruins in Overseer. You have a 9x9 grid (made up of 3x3 mini-grids), you have the numbers 1-9, but can only set up the problem with one of each number in the grid. You can only have one number per each row and column, and only one number per mini-grid. Is it solvable? How should I know? I never got past intermediate. But it would be fun to see who could work it to the desired pattern.
Hammerhead
Hammerhead
I thought the brick puzzle in TMO was a version of a chess-puzzle, placing eight queens on the board without them putting any other queen in check. I believe a similar puzzle was in fact used in The 7th Guest, if I recall correctly.
-Fred
-Fred
Pirates, vampires, zombies, ninjas, ghouls, aliens, goblins, monsters, robots, sorcerers, undead, werewolves, demons, mutated dinosaur-cyborgs and those pesky phone salesmen! The shotgun is a one-size-fits-all solution!
