Exclude based on 'colors'?!

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

Exclude based on 'colors'?!

Postby mat » Fri Jul 06, 2012 2:45 pm

Hi :)

Image

What does colors have to do with sudoku? :S
Which solving technique do I need to solve the next step?

Thanks in advance!

Source of this sudoku: Stefan Heine - schwierig bis extrem 1 - p.129)
mat
 
Posts: 1
Joined: 06 July 2012

Re: Exclude based on 'colors'?!

Postby JasonLion » Fri Jul 06, 2012 3:52 pm

There is a whole family of solving techniques called "coloring" in Sudoku. See for example the Sudopedia entry. I suspect they are referring to simple coloring in your example.
User avatar
JasonLion
2017 Supporter
 
Posts: 642
Joined: 25 October 2007
Location: Silver Spring, MD, USA

Re: Exclude based on 'colors'?!

Postby champagne » Sat Jul 07, 2012 4:20 pm

In that specific case, a candidate '6' is in each coloured cell and is in bi-value in one row, column or box.

All green or all cyan are true.

The cyan can not be true due to conflicts, so '6' green is true.

You can do the same with chains, but this is a way to expand the chains
champagne
2017 Supporter
 
Posts: 7352
Joined: 02 August 2007
Location: France Brittany


Return to Help with puzzles and solving techniques

cron