Thursday, August 25, 2011

Sudoku Mastery

I have been an on-and-off sudoku practitioner. Right now, I am in one of those sudoku fixation periods. I've gotten to the point that the challenge for me, even for the most difficult sudoku puzzles, is to complete the puzzle without making any notations in the margins or in the boxes themselves. I try to keep the patterns and counts in my mind. And I've gotten pretty good at it. So good, in fact, that it is not a question of my being able to solve any puzzle, but rather how quickly I can do it. So, if I really want to push myself with the game, I time myself to see how many minutes it takes me to do a puzzle from start to finish.

I got to this point, though, not because of any particular intellectual ability. Rather, it is through repetition and increased familiarity with the patterns of logic particular to this specific kind of puzzle. If I would give a tip to any sudoku aficionado who would like to improve his or her facility in puzzle solving, it would be this: don't work with single numbers, but with clusters of numbers, as many as you can hold in your mind's eye. For example, when you look at a row of nine squares, perhaps there are 3 numbers that are visible in that row. If you can memorize the 6 numbers that are missing in that row and hold that number combination in your mind as you cross tabulate those six numbers with all of the numbers in the 9 columns, you will more often than not be able to go through a process of elimination that could give you the one number of the six that fits in a particular square of that row.

I know it sounds kinda cryptic, but just keep in mind the idea of working with sets of numbers as opposed to single numbers and I think the value of doing that will become apparent and your sudoku puzzle solving abilities will grow exponentially.


Eric said...

Thanks for the tip! I am a Sunday morning sudokuer, and I employed your method on today's puzzle. Not only did I manage to finish it without any corner notes (a first), but I do so a little faster than usual.

Huck said...

That's great, Eric! I remember when this way of solving puzzles came to me. It was a kind of "a-ha!" moment of clarity. What's happening now in my evolution of sudoku puzzle-solving, which I think is a by-product of this "a-ha!" moment, is that I am not only able to keep clusters of unassigned numbers in mind, but also to remember patterns of what you call corner notes across the entire sudoku board at the same time that I laser in on a cluster of unassigned numbers for a particular row, column, or nine-box sector of the puzzle.