## colors-confused

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

### colors-confused

I tutorialed this site to learn colors:
http://angusj.com/sudoku/hints.php

But the advice was pertaining to cells that only had two possible values.
This 'colors' step is dealing with more than that

***Sudoku from "Simple Sudoku" Expert Level

I am confused as I am only used to 'colors' when there are only 2 values possible in each cell.
For instance...
Why is the suggestion here to eliminate 5's and not 4's?
What cell did you begin the first coloring in?
What was the tip off to use colors?

Any other info would be appreciated, as I am a newbie to this expert level, but I pick up
fast and really enjoy the tougher Sudokus.

Thanks,

LTP
lovethepirk

Posts: 8
Joined: 22 February 2006

I think I got it...Let's see if this is correct...

Only color the number(5 in this case) that only have two possibilities per row/column.

So the only colors needed here would be this:

And hence we see that b/c there are two greens in box 1 then they cannot be 5. So we see
that R2C3=>5 and the puzzle now solves itself.

Is this correct?

Also Does this method just eliminate the '5's from box 1 or does it say there must be a '5'
in R8C1(I know a 5 goes there through deduction but could I just throw one in there since it
is blue)?

LTP
lovethepirk

Posts: 8
Joined: 22 February 2006

LTP wrote:Does this method just eliminate the '5's from box 1 or does it say there must be a '5' in R8C1
You mean r9c1.

LTP wrote:(I know a 5 goes there through deduction but could I just throw one in there since it is blue)?

Well, it's confusing because you switched the colours in the two posts. Take your second post. Colouring eliminates the 5s from box 1 because there are 2 greens - therefore all your greens are now false and the blues are true.

If you had coloured all the 5s - as in the first post - then you could have eliminated all five originally blue 5s.
emm

Posts: 987
Joined: 02 July 2005

When two cells with the same color end up sharing a group, then you know that color must be false and the opposite color must be true. ALL the cells marked with the opposite color can be assigned the value 5.

Tracy
TKiel

Posts: 209
Joined: 05 January 2006

TKiel wrote:When two cells with the same color end up sharing a group,

Does the word "group" in your statement mean a box as in this case or could it mean a row or column too?

Thanks,

LTP

And thank you to em for posting
lovethepirk

Posts: 8
Joined: 22 February 2006

LTP,

Yes, in this case it means a box, but it could also mean a row or a column.

Tracy
TKiel

Posts: 209
Joined: 05 January 2006