Sudoku Skill Meter

The program offers you to solve a number of tasks and compare your results with other participants.
It contains 100 tasks average and above-average level of complexity. All tasks have a unique solution, and formed by "honest" algorithm based on the random number generator.
Before sending the user an initial task undergoes transformation, not leading to a change in its complexity, so the user can take several attempts to improve the result. a new version of the same job he will be offered at each attempt.
Game time is recorded by the server clock, so it may be slightly different from what the user sees on his device.
User rating to a particular game is calculated as the ratio of the time averaged over all the players in the last 30 days, to the time taken specific participant. For example, a rating of 1.5 would mean that user has solved the task 1.5 times faster than the average for this game. Rating of 0.5 means that the task took twice as long than the average participant.
Overall rating of the participant is defined as the average rating of all games in which he participated.