The New Sudoku Players' Forum

[urhegyi]

This is a sudoku rated SE9.0(much too extreme) but gets only a score of 408 on https://www.sudokuwiki.org//
Anyone knows why?
For me it's much too hard.

Code: Select all

1.......6.2..4.......3.2.5......13......5...74.69..8....5..64.2.3..7..9.8........

[Hajime]

I don't know the rating-system of SudokuWiki . Is 408 low or high? It also mentions "extreme".
He needs 7 AIC's and 4 Cell Forcings chains Type 2.
I think AIC's are not in SE ??

SE needs also lot of chains:
11 x Forcing Chain (7,1-7,3) 1 x Nishio Forcing Chains (7,8) 2 x Region Forcing Chains (8,2-8,4) 2 x Cell Forcing Chains (8,5) 1 x Dynamic Cell Forcing Chains (8,9) 2 x Dynamic Region Forcing Chains (8,9-9,0)

Indeed way above my skills.

[m_b_metcalf]

Just to note that 9r2c1 is a backdoor solution.

Mike

[Mathimagics]

No hidden tags around that P&P spoiler, Mike? Shame on you!

[mith]

sudokuwiki's rating is based on summing scores for each step (a little more complicated than Hodoku's rating, which just gives a fixed score for each technique, the number of eliminations is factored in somehow and maybe some other stuff). It's somewhat useful for the sort of puzzle you might see in a newspaper, but practically arbitrary otherwise. Fish steps in particular get super inflated ratings; this puzzle (which just needs basics and fish) is the highest rating I'm aware of (2257): http://forum.enjoysudoku.com/the-final-countdown-2-t38801.html (Unlike Hodoku, if it can't solve it with supported logical steps it won't rate it, so at least you don't get the crazy "how many brute force steps did it use for this particular morph" ratings.)

408 is pretty hard, if there aren't fish inflating it.