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### How I Solved Sudoku With a Business Rules Engine - KDnuggets

On a family trip a few months back, I was flipping through an airline magazine and landed on the puzzles page. There were three puzzles, "Easy", "Medium", and "Hard". At the top of the page a word that would become my obsession over the next couple of months: "Sudoku". I had heard about Sudoku puzzles, but I had never really considered trying one. I grabbed a pencil from one of the kids and started with the "Easy" puzzle. It took me quite some time (and I tore the paper in one spot after erasing too many times) but I eventually completed the puzzle.

### Sudoku Puzzles

In the AI History Sudoku, each row, each column, and each 3x3 box must contain every number from 1 to 9. In the Letter Sudoku, each row, each column, and each 3x3 box must contain each of the 9 different letters. If completed properly, a nine letter word will be revealed.

### Solve Sudoku Puzzle Using Deep Learning, OpenCV And Backtracking

The sudoku game is something almost everyone plays either on a daily basis or at least once in a while. The game consists of a 9 9 board with numbers and blanks on it. The goal is to fill the blank spaces with suitable numbers. These numbers can be filled keeping in mind some rules. The rule for filling these empty spaces is that the number should not appear in the same row, same column or in the same 3 3 grid.

### OpenCV Sudoku Solver and OCR - PyImageSearch

In this tutorial, you will create an automatic Sudoku puzzle solver using OpenCV, Deep Learning, and Optical Character Recognition (OCR). My wife is a huge Sudoku nerd. Every time we travel, whether it be a 45-minute flight from Philadelphia to Albany or a 6-hour transcontinental flight to California, she always has a Sudoku puzzle with her. The funny thing is, she prefers the printed Sudoku puzzle books. She hates the digital/smartphone app versions and refuses to play them. I'm not a big puzzle person myself, but one time, we were sitting on a flight, and I asked: How do you know if you solved the puzzle correctly?

### Solving Every Sudoku Puzzle

Unfortunately, this is not a true Sudoku puzzle because it has multiple solutions. But is this an intrinsicly hard puzzle? Or is the difficulty an artifact of the particular variable- and value-ordering scheme used by my search routine? To test I randomized the value ordering (I changed for d in values[s] in the last line of search to be for d in shuffled(values[s]) and implemented shuffled using random.shuffle). The results were starkly bimodal: in 27 out of 30 trials the puzzle took less than 0.02 seconds, while each of the other 3 trials took just about 190 seconds (about 10,000 times longer).