Frog Number Place かえるのナンプレ

Just good! It is the difficulty of Sudoku.

Just right! Just exercise the difficulty problem of the head just as quickly as you exercise at the head. I will not make a question that I can not solve if I do not know the definite stone. If you think carefully, we only ask questions that can be solved.

There is also a function that automatically solves, and this will depend on Cho! Any problem is solved within one second. You can also set and solve problems. When I set up a problem which is said to be the most difficult in the world made by a mathematician of Finland, I was able to solve it in less than 1 second.

There is also a hint function.