Sudoku Players' Forum (clone)

Hello, if you look at the above image, you''ll see that I have identified what I believe to be a skyscraper with those four green 3's. Those two red 3's see both ends of the skyscraper and are the ones that should be removed. Everything looks right to me but it's wrong. The lower red 3 is an actual 3 and shouldn't be removed, therefore I don't know what I'm doing

Why isn't that a skyscraper?
Thanks

in a skyscraper, we have 2 bi-values sharing one row/column.
this not at all what you show, but the digit "3" has some potential put r9c5 in "cyan" , you'll see a sky-scraper
a bi-value can not have twice the same color in the way you show it

Hi GlassWizzard,

I think you missed the 3 candidate in r4c6.
As champagne says, there is a skyscraper on 3s, I would add that the 3s you have marked in r9 are part of it.

champagne wrote:a bi-value can not have twice the same color in the way you show it

Only in coloring chains (which is a valid POV here), but as a mere highlighting there is no reason to use different colors.

Marek

marek stefanik wrote:, but as a mere highlighting there is no reason to use different colors.Marek

Yes, coloring does not help for sky scrapers (several possibilities here, with or without groups of candidates)
My point was that the coloring done here has no clear logic for me
EDIT

some of the sky scrapers

c2;c5 <3r9c1>
r5r9 <3r7c6>
r3r7 (group) <3r5c6>
...
c2c6 (group)
r5r7

and in coloring mode, after r9c5 put in the right color, you see a turbot in row 4 (twice the green color)

Oh that 3, I see now, yes I totally missed it Thanks for the insight.