Indexification (Dyn Fog)
(Published on 4. February 2025, 15:19 by Fenners)
I normally get quite boggled with index cells, so I thought I'd have some practise setting a puzzle with it as a prominent rule. I found by the end it started to sink in! Also, learnt to implement dynamic fog for the first time!! Enjoy and any feedback very much welcomed.
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Puzzle: Indexification
Rules:
Normal 9x9 Sudoku rules apply. Place the digits 1-9 once each in every row, column and 3x3 box.
Dynamic Fog: Correctly placed digits may or may not clear fog from the grid.
German Whispers: Adjacent digits along a green line must differ by at least 5.
Killer Cages: Digits in a cage cannot repeat
Indexers: A blue cell in row X indicates the row where X appears in the column. A red cell in column Y indicates the column where Y appears in the row. A blue AND red cell acts as a blue cell and a red cell at the same time.
Solution code: Row 9, left to right, no spaces:
Comments
on 27. April 2025, 10:26 by TeddieMilo
A bit confusing at the beginning about the indexing rule but got adapted and becoming more fun.
Maybe next time can give some exanples for better clarity.
TQ!
on 26. March 2025, 01:27 by ostio456
I finished, I loved it, yet I am still clueless on indexing. Might take me some time to infiltrate this indexing business.
on 14. February 2025, 23:11 by dzamie
Nice! Dynamic fog works really well with this. My only troubles were self-inflicted: forgetting which color went to which axis.
on 6. February 2025, 02:11 by fishsaltyak
So much fun!
on 5. February 2025, 21:34 by rainingfish
The use of the dynamic fog had me second guessing myself at first, but once I got going I found the various constraints interacted quite beautifully!
on 5. February 2025, 04:12 by kirb
I agree that this was certainly challenging for someone unfamiliar with indexing (i.e. me!). It took me a while to figure out, but afterwards was a very nice solve :)
on 5. February 2025, 00:39 by MarthaB
Fantastic puzzle!
on 4. February 2025, 23:42 by mmm
I don't understand the indexer rule. Could someone explain it to me? maybe with an example
Fenners: Take the red cell in the bottom left of the visible box. This is in column 4. Place a 7 in it. Then the 4 must go in cell 7 of that row. Now place a 2 in it. Then the 4 must go in column 2 of that row. The same is true for the cyan cell in the upper corner except it indexes the column. This cyan cell is in row 4. Place a 7 in it. Then the 4 goes in cell 7 of that column. Place a 2 in it. Then the 4 goes in cell 2 of that column.
Think where does the digit go along the row (R) for red (R). Think where does the digit go down the column (C) for cyan (C). I know it's more of a blue but it helps me remember.
on 4. February 2025, 22:22 by therealsillypenguin
Great puzzle! Personally, I disagree with the below commenter, and think 1* is fair, as it's pretty easy if you're familiar with index puzzles.
on 4. February 2025, 20:35 by PinkNickels
Very fun! Clever setting.
on 4. February 2025, 20:29 by anyeyeball
I love indexing sudoku, and this is a great one. Thanks for sharing.
on 4. February 2025, 20:28 by softie
That was certainly mind-boggling. No way is it 1*!
Fenners: I originally categorised it as as 2* but the people have spoken. I think it could go either way depending on familiarity with indexing.
on 4. February 2025, 18:01 by Wuschel
Beautiful, great use of fog. I loved the striped cells.
