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Sudoku - sharing skills
- Thread starter 2020hindsight
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hey les,
Maybe I'll just have to accept the fact that I can do medium and hard, but at this point in my life at least, I can do no evil
Maybe I'll just have to accept the fact that I can do medium and hard, but at this point in my life at least, I can do no evil
2020,
Just takes time to get used to the evil puzzles, but use the lower levels to gain experience. and try different approaches out.
I have included a link to a web page on Sudoku hints that you may find useful below:
http://angusj.com/sudoku/hints.php
It explains pairs, triples and quads (hidden and naked).
I have included a copy of the same 'evil' puzzle and taken a different approach to solving it.
You will note that in R8 C5&6 that these cells contain '4,7' & '4,7,8' respectively. You can remove the '8' from R8C6, as you have actually have a pair in those two cells. The '4' can be removed from R8C2, etc.
Try it and see how you go from there.
Have fun.
Just takes time to get used to the evil puzzles, but use the lower levels to gain experience. and try different approaches out.
I have included a link to a web page on Sudoku hints that you may find useful below:
http://angusj.com/sudoku/hints.php
It explains pairs, triples and quads (hidden and naked).
I have included a copy of the same 'evil' puzzle and taken a different approach to solving it.
You will note that in R8 C5&6 that these cells contain '4,7' & '4,7,8' respectively. You can remove the '8' from R8C6, as you have actually have a pair in those two cells. The '4' can be removed from R8C2, etc.
Try it and see how you go from there.
Have fun.
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Hi Rushiat,
Good to see you join in. Used to use the full notation approach when starting to learn Sudoku, but have reduce using it to assist in identify candidates in rows, columns or squares.
A number of the Sudoku games allow you to pencil in the full set of numbers from 1 to 9. Whereas, WebSudoku permits only '5' numbers to be pencilled in. May as well leave the cell blank and when more numbers are discoverd consider pencilling the missing numbers into the cell, as required.
When trying to beat the clock on Sudoku you need to minimise notating potential candidate numbers unless it is necessary, as this really slows you down.
Cheers.
Good to see you join in. Used to use the full notation approach when starting to learn Sudoku, but have reduce using it to assist in identify candidates in rows, columns or squares.
A number of the Sudoku games allow you to pencil in the full set of numbers from 1 to 9. Whereas, WebSudoku permits only '5' numbers to be pencilled in. May as well leave the cell blank and when more numbers are discoverd consider pencilling the missing numbers into the cell, as required.
When trying to beat the clock on Sudoku you need to minimise notating potential candidate numbers unless it is necessary, as this really slows you down.
Cheers.
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thanks les
I'll study it when I have some spare time
have a great NY
Suspect I'll be working harder next year, trying to master some new software at work etc - still might fit in the odd sudoku
btw, If you're ever on a Qantas plane, and you hear someone in economy class scream out "Yahooooo !! Beudyy!! - GOT YOU OUT, YOU BAS-TARD!! " ... - it'll be me.
cheers 2020
I'll study it when I have some spare time
have a great NY
Suspect I'll be working harder next year, trying to master some new software at work etc - still might fit in the odd sudoku
btw, If you're ever on a Qantas plane, and you hear someone in economy class scream out "Yahooooo !! Beudyy!! - GOT YOU OUT, YOU BAS-TARD!! " ... - it'll be me.
cheers 2020
thanks les
btw, If you're ever on a Qantas plane, and you hear someone in economy class scream out "Yahooooo !! Beudyy!! - GOT YOU OUT, YOU BAS-TARD!! " ... - it'll be me.
cheers 2020
Be careful they don't think it's a terrorist, especially in today's environment
You can start the puzzles in varies ways and still arrive at the same final same result. Some approaches are faster than others.
Sometimes you appear to get stymied on a puzzle and then all of a sudden see the light, wonder how you overlooked it, and make progress again.
All the best for the New Year.
Any questions let me know.
Cheers.
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yep - like the time I saw my mate Jack a few seats away - and I called out Hi.
btw, if you can see a way forward from that predicament I ended up in (back there a few posts, #61), I'd appreciate it. cheers. no hurry - some time this year maybe lol.
yep - like the time I saw my mate Jack a few seats away - and I called out Hi.
btw, if you can see a way forward from that predicament I ended up in (back there a few posts, #61), I'd appreciate it. cheers. no hurry - some time this year maybe lol.
You will note that in R8 C5&6 that these cells contain '4,7' & '4,7,8' respectively. You can remove the '8' from R8C6, as you have actually have a pair in those two cells.
Cheers.
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great site ... simple sudoku :-
http://simple-sudoku.en.softonic.com/
Even when the computer gives you a massive clue, it still isn't obvious, lol.
I mean , a decision can be made about the highlighted cell ( obtained by hitting the yellow question mark = hint.)
Lower left it says " Exclude based on multiple colours".
Note that every square with a 9 in it is coloured green ( or some other colour)
so
a) what number can be excluded? , and
b) why?
Now try doing that without the computer to give you all the candidates, and also look for the colour patterns ( multiple colour patterns in this case)
(i.e. Hence I think I'm convinced that you can only get some out with the help of a computer.)
http://simple-sudoku.en.softonic.com/
Even when the computer gives you a massive clue, it still isn't obvious, lol.
I mean , a decision can be made about the highlighted cell ( obtained by hitting the yellow question mark = hint.)
Lower left it says " Exclude based on multiple colours".
Note that every square with a 9 in it is coloured green ( or some other colour)
so
a) what number can be excluded? , and
b) why?
Now try doing that without the computer to give you all the candidates, and also look for the colour patterns ( multiple colour patterns in this case)
(i.e. Hence I think I'm convinced that you can only get some out with the help of a computer.
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I mean, even if you've coloured in your INFlight magazine with all the possible "9" squares, you get this :-
and you have to work out that there's a decision that can be made about the highlighted square. (you're brighter than I am if you can see that one )
PS Simple Sudoku give 5 grades :-
Easy Standard Hard Expert and Extreme. This is from an extreme one.
PS In Flight magazines fortunately don;t go to the extreme.
(PS sorry if my earlier post - first draft was confusing)
and you have to work out that there's a decision that can be made about the highlighted square.
(you're brighter than I am if you can see that one )PS Simple Sudoku give 5 grades :-
Easy Standard Hard Expert and Extreme. This is from an extreme one.
PS In Flight magazines fortunately don;t go to the extreme.
(PS sorry if my earlier post - first draft was confusing)
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OK if you read the clues attached to the simple sudoku program, you find this explanation ...
Blue and Lime cells, one set is "true" the other not.
Pink and Brown , ditto.
(in each case there are only 2 options in a row or column or "square")
Then - because Pink and Blue are on same column, then
"Pink and Blue cannot both be true,
therefore their opposites ( i.e. Brown and Lime) cannot both be untrue,
ie. one of Brown or Lime is true.
Therefore the highlighted cell (common to both brown and lime) is untrue.
Conclusion : You can delete 9 as a candidate for that cell.
Sheesh - and that's a breakthrough at this level lol.
Like I say, you need a computer, or a real lot of time.
Blue and Lime cells, one set is "true" the other not.
Pink and Brown , ditto.
(in each case there are only 2 options in a row or column or "square")
Then - because Pink and Blue are on same column, then
"Pink and Blue cannot both be true,
therefore their opposites ( i.e. Brown and Lime) cannot both be untrue,
ie. one of Brown or Lime is true.
Therefore the highlighted cell (common to both brown and lime) is untrue.
Conclusion : You can delete 9 as a candidate for that cell.
Sheesh - and that's a breakthrough at this level lol.
Like I say, you need a computer, or a real lot of time.
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Hi , I have become a Sudoku fan but have got to a level where alas I am stuck. Talked to a friend who completes all the evils and he told me you get to a level where you have to take a guess to continue on. He places a dot in the corner of where his first guess is and works forward and back from that point.
Too hard for me to cope with this, nearly gone cross eyed with staring and rubbing with my mechanical pencil
Too hard for me to cope with this, nearly gone cross eyed with staring and rubbing with my mechanical pencil
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sh#t!! - why didn't I think of that ?? !! lol
but you're right - life's arguably too short for this nonsense.
(then again - it's as good as watching "Dancing with the stars"
PS Actually - and in truth, I'm a bit of a purist. If I type "4" on a cell that has the option of say 4, 9, or 2 - and if it is accepted , (meaning it was a lucky guess), - and then I realise my logic was flawed, I will "undo ( = Cntl+Z) and persist in trying to "crack the code".
But as I conclude back there - in some cases I reckon your friend is right - either use a computer, or use "trial and error". - cheers m8
bigdog
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Sudoku fans
Please try the free training sudoku lessons based on the 1 to 9 technique.
I purchased the full package and found very good.
http://www.sudokuprofessor.com/thanks
Lesson #1:
http://www.sudokuprofessor.com/1stVideoLesson.php
Lesson #2:
http://www.sudokuprofessor.com/2ndVideoLesson494.php
Lesson #3:
http://www.sudokuprofessor.com/3rdVideoLesson648.php
Lesson #4:
http://www.sudokuprofessor.com/4thVideoLesson836.php
Lesson #5:
http://www.sudokuprofessor.com/5thVideoLesson428.php
231
Please try the free training sudoku lessons based on the 1 to 9 technique.
I purchased the full package and found very good.
http://www.sudokuprofessor.com/thanks
Lesson #1:
http://www.sudokuprofessor.com/1stVideoLesson.php
Lesson #2:
http://www.sudokuprofessor.com/2ndVideoLesson494.php
Lesson #3:
http://www.sudokuprofessor.com/3rdVideoLesson648.php
Lesson #4:
http://www.sudokuprofessor.com/4thVideoLesson836.php
Lesson #5:
http://www.sudokuprofessor.com/5thVideoLesson428.php
231
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Question, bigdog ( and remember I've already admitted I couldn't progress that puzzle on post #71 without a computer, where I can use the multiple colour stuff - and where, with the click of F10 key, you can ask for eg "all cells with 9 as a candidate" - as on the previous post, #70)
but getting back to that question ....
could you (or the good professor - looks like a humourous dude ) advance that puzzle from it's current position?
(Let me tell you - it's a stinker! - or maybe you can show me that it isn't)
cheers 2020
PS I'll understand if you don't take this challenge - it will take a while. (imo anyway).
but getting back to that question ....
could you (or the good professor - looks like a humourous dude
) advance that puzzle from it's current position?(Let me tell you - it's a stinker! - or maybe you can show me that it isn't)
cheers 2020
PS I'll understand if you don't take this challenge - it will take a while. (imo anyway).
bigdog
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Question, bigdog ( and remember I've already admitted I couldn't progress that puzzle on post #71 without a computer, where I can use the multiple colour stuff - and where, with the click of F10 key, you can ask for eg "all cells with 9 as a candidate" - as on the previous post, #70)
but getting back to that question ....
could you (or the good professor - looks like a humourous dude
(Let me tell you - it's a stinker! - or maybe you can show me that it isn't)
cheers 2020
PS I'll understand if you don't take this challenge - it will take a while. (imo anyway).
2020, I was able to complete #70 using the 1 to 9 technique.
-- It took quite a bit of time!
-- you only record two possible numbers only
-- you do not record three or more numbers
-- start from finding possible 1's, then 2's on to 9's
The yellow square for #71 = 6
Can you access the videos?
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bigdog
well done if you did it unaided. (exceedingly well done imo)
cheers - (videos later)
bigdog
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2020,
71#
Please review the video's for the technique and then try the following to find the only places two for numbers.
First complete 1's
- Top five rows 1's have been completed
- Row six column four and five is the only place for 1's
- Row seven column four and five is the only place for 1's
- Bottom two rows 1's have been completed
The 2's have been completed for all rows
Complete 3's where possible
- 3's for rows four to ninth have all been completed
- There are no 3's in the first three rows
- column 2 rows 1 and 3
- column 8 rows 2 and 3
- column 4 (3's could be in rows 1, 2 or 3)
Complete 5's where possible
- row 1 column 1 and 2
- row 6 column 5 and 6
- column 6 rows 7 and 8
- column 7 rows 8 and 9
Complete 6's where possible
- row 3 column 5 and 6
- row 6 column 5 and 6
Complete 7's where possible
- row 3 column 4 and 6
- row 4 column 4 and 6
Complete 8's where possible
- row 1 column 9
- row 3 column 8
- row 7 columns 4 , 5 or 6 (all three possible)
- therefore row 9 columns 8 and 9 must be 8
Complete the missing numbers where there are seven numbers in a box
- row 5 column 2 = 4 9 (are the only possibles)
- row 6 column 1 = 4 9 (are the only possibles)
- row 4 column 7 = 4 9 (are the only possibles)
- row 5 column 8 = 4 9 (are the only possibles)
- row 7 column 2 = 5 9 (are the only possibles)
- row 9 column 1 = 5 9 (are the only possibles)
71#
Please review the video's for the technique and then try the following to find the only places two for numbers.
First complete 1's
- Top five rows 1's have been completed
- Row six column four and five is the only place for 1's
- Row seven column four and five is the only place for 1's
- Bottom two rows 1's have been completed
The 2's have been completed for all rows
Complete 3's where possible
- 3's for rows four to ninth have all been completed
- There are no 3's in the first three rows
- column 2 rows 1 and 3
- column 8 rows 2 and 3
- column 4 (3's could be in rows 1, 2 or 3)
Complete 5's where possible
- row 1 column 1 and 2
- row 6 column 5 and 6
- column 6 rows 7 and 8
- column 7 rows 8 and 9
Complete 6's where possible
- row 3 column 5 and 6
- row 6 column 5 and 6
Complete 7's where possible
- row 3 column 4 and 6
- row 4 column 4 and 6
Complete 8's where possible
- row 1 column 9
- row 3 column 8
- row 7 columns 4 , 5 or 6 (all three possible)
- therefore row 9 columns 8 and 9 must be 8
Complete the missing numbers where there are seven numbers in a box
- row 5 column 2 = 4 9 (are the only possibles)
- row 6 column 1 = 4 9 (are the only possibles)
- row 4 column 7 = 4 9 (are the only possibles)
- row 5 column 8 = 4 9 (are the only possibles)
- row 7 column 2 = 5 9 (are the only possibles)
- row 9 column 1 = 5 9 (are the only possibles)
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