Sudoku rules:

For the most common type of Sudoku (n=9), as displayed in figure 1, there are 9 sub-squares with 9 fields each. Every row and column has 9 fields. To solve a Suodoku game, nine different numbers (from one to nine) have to be placed within the fields so that the three following rules are not broken:

In each row no number is allowed to appear twice

In each column no number is allowed to appear twice

In each sub-square no number is allowed to appear twice

As soon as all different numbers are placed exactly once in each row, column and sub-square, the Sudoku riddle is completed. Figure 2 shows examples of allowed and forbidden steps in a Sudoku grid.

Depending on the degree of difficulty a certain amount of numbers is given when a game is started.

For the most common type of Sudoku (n=9), as displayed in figure 1, there are 9 sub-squares with 9 fields each. Every row and column has 9 fields. To solve a Suodoku game, nine different numbers (from one to nine) have to be placed within the fields so that the three following rules are not broken:

In each row no number is allowed to appear twice

In each column no number is allowed to appear twice

In each sub-square no number is allowed to appear twice

As soon as all different numbers are placed exactly once in each row, column and sub-square, the Sudoku riddle is completed. Figure 2 shows examples of allowed and forbidden steps in a Sudoku grid.

Depending on the degree of difficulty a certain amount of numbers is given when a game is started.