Classic Sudoku(002)
(Published on 1. September 2020, 12:23 by cdwg2000)
Rules: Classic Sudoku rules apply.
The author of the puzzle is my friend 胡蒙汀(Hu Meng Ting) from China. I hope you like it and would appreciate any feedback.Special note: To complete this nightmare level puzzle, you need to use an intuitive skill (SK-Loop) of Classic Sudoku. Even if you are familiar with the skill, it is difficult to observe, so the difficulty is set as 5 stars. If you can't find a solution, I suggest you check the 5 previously published puzzles, they also apply the intuitive skills of problem Sk-Loop.
The numbers in columns 1, 3, 7, and 9 and rows 2, 4, 6, and 8 are all 4 groups 1-9. The yellow numbers 1 and 3 are offset. The purple is the common cell where the rows and columns meet, and the corresponding column is red. The {1289} will be filled in the red cell of the corresponding row, and the same is true: the blue {4567} of the corresponding row will be filled in the blue cell of the corresponding column. As shown in the picture, this is an important spoiler, without it, it may be difficult to move an inch! After this, an X-Wing of 5, an Xy-Wing of {469}, and a unique rectangle of {28} may be applied. This is a five-star puzzle!
Solution code: Row 7, followed by coloum 2.
Comments
on 22. April 2021, 09:31 by cdwg2000
A key problem-solving point has been added. This is a spoiler. If you don’t like this approach, please let me know.
on 9. January 2021, 04:11 by cdwg2000
You can follow Tom Collyer's personal blog for related discussions: https://tcollyer.blogspot.com/2020/10/the-msls-revolutions.html.
https://tcollyer.blogspot.com/2020/09/puzzle-350-sudoku.html
on 13. September 2020, 16:00 by Realshaggy
Almost all solvers solved it when there were no hints at all. I agree that this is a general problem of the rating system, but it's a hard one to fix.
This is the equivalent of a very hard chess study you only understand after it is explained by a GM.
It breaks with the right guess, but before, even Andrew Stuarts solver throws the towel and can't calculate a difficulty rating because it can't find a path.
on 13. September 2020, 12:21 by Puzzle_Maestro
I have to say that I am very much disappointed by the low rating on this sudoku. The key idea is a very beautiful one!
on 10. September 2020, 17:25 by detuned
Absolutely fascinating - this puzzle breaks scanraid. I'm not sure I've fully understood what is going on, but it's clear this puzzle is a gateway into previously poorly understood structures woven into the fabric of Sudoku. Thanks for sharing!
