Sudoku

The program has a database of 34,880 games. Each of them can be entered in many different ways in different difficulty levels. Each difficulty level is determined by the number of fields that will be randomly revealed. Links between fields are not taken into account.
In addition, connoisseurs have the option of determining how many fields they want to uncover to start with.

If you don't know which way to go, you can have any field hinted or just show errors.

Tip: If you are not comfortable with the preset difficulty levels, you can easily change them. In the obtiz.txt file, there are 5 values written in lines that represent the number of fields to reveal for each difficulty, starting with very easy.
Make sure to enter valid values. For the game to have just one solution, there should be at least 17 uncovered numbers.

The program also allows you to print the games.