If you started with easy Sudoku, you will soon realize that you have become too quick to deal with these puzzles and want more! At this point, you can move to medium level Sudoku. The rules remain the same for medium Sudoku puzzles. The number from one to nine can appear only once in each of the 9 3x3 squares, in each individual line and in each column. The difference is only in the number of originally displayed figures.
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