Sudoku

[gollob]

With Suduku puzzles how are they graded like as mild, hard or fiendish

[murraymints]

cos some are just a b u ** e r to do !

[Old_Geezer]

I think it depends on what tactics/rules you need to use to solve them ?
Often it seems they are misgraded anyway.

[-SharonA-]

Easy to do - these are mild ones
Completing in pencil with lots of rubbing out - these are the hard ones
Paper ripped up and put in bin - these are the fiendish ones

[rsvp]

the ones I do are gentle, moderate, hard and diabolical

[jomifl]

There are different orders of logic necessary to solve them.The easy ones just require the elimination of other numbers until there is only one candidate for a given box, The moderate ones require elimination of some candidates because they must be in other boxes even if you don't know exactly which ones and the difficult ones I haven't got a clue about..

[Togo]

The very hard ones are usually a combination of elimination and squares that can only be either or. Now it gets hard. What I do is try the options when it can only be one of two numbers. Sometimes you have to 'carry' up to four or five possible squares resolutions until you find that you have a square or column that cannot resolve if you choose that first option, so the other option must be the one. No cheating is allowed, it all must be done in your head. It is a great short term memory exercise. This weeks Sunday Times Hard No. 992 and Very Hard No. 993 I get as, reading top to bottom, the shaded squares to be 6,6,3. and 5,8,8.

[Togo]

http://www.sudoku9x9.com/sudoku_solving_techniques_9x9.html

This site explains all the techniques employed, names them, and explains them.

[Old_Geezer]

In my experience newspapers don't do difficult ones. The app on my mobile does though. It's better there because it puts in small 'pencilled' values as requested and rubs them out again when asked with no smudge left.