Can't find nice loops

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Can't find nice loops

Postby Sam Kennedy » Sun Apr 30, 2017 10:57 pm

I'm currently using hodoku and use candidate colouring to highlight strong links. When I try and find loops, I use notepad/gedit, pick a cell, and then start seeing where I can get from there, and then try and make my way back to the starting cell. However I can rarely find a loop, and if I do, it doesn't eliminate any candidates. I've also tried using image editing software to draw lines across the sudoku grid, but this gets messy really quickly.

When finding AICs/nice loops, how do you do it? Just lots of trial and error? Any tips on how to find useful loops? I'm considering getting a pen and paper and doing the equivalent of a depth first search on every possible link, but this brute force method doesn't seem like it would be the best way to approach this.

Any advice would be greatly appreciated :)
Sam Kennedy
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Joined: 15 June 2016

Re: Can't find nice loops

Postby StrmCkr » Mon May 01, 2017 6:38 am

Most of them are found via computer aided searching.
For the most part keep the search size down to 2 digits with up to 4 links.

Usually starting with a cell with 2 options (bi valve) Or a strong link (2 spots in a sector, row, col, box)
The most common small nice loops are named.


After that it's pretty much trial and error but all of them start or end at a strong link,
So that's where I'd suggest starting.

(ps yes alot of them do not have eliminations as well)
Some do, some teach, the rest look it up.
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