Can't find nice loops

Post the puzzle or solving technique that's causing you trouble and someone will help

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
 
Posts: 3
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.

W-wing
M-wing
S-wing
L-wing
H-wing

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.
User avatar
StrmCkr
 
Posts: 604
Joined: 05 September 2006


Return to Help with puzzles and solving techniques