Good Old Sudoku 1.0

The most popular logic puzzle in Japan. It is very simple to learn, requires no calculations, and provides a surprisingly wide variety of logic situations. The rules are simple. Each row, column and minibox comprises the numbers 1 through 9. The solver must complete the missing numbers. So the completion rules are so simple and yet the overall task can be difficult. Sudoku is recommended by some teachers as an exercise in logical reasoning.