Cops & Robbers
(Published on 21. October 2025, 07:22 by SennyK)
I hope you will enjoy my third puzzle! I am very proud of it :-)
I would be really grateful for all the comments and ratings.
Normal sudoku rules apply.
Killer: Digits in a cage may not repeat.
Sandwich: A clue outside the grid gives the sum of the digits appearing between the 1 and the 9 in that row/column.
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Prison: Cages represent prisons. One full cage is one prison.
Roles:Police: Digits 1 and 9 are cops - they cannot go to the prison (i.e., digits 1 and 9 cannot appear in cages).
Criminal group: Digits 4, 5 and 6 are robbers. The number of robbers in the prison(s) in the box equals the power of the police in that box.
Unlucky fellows: Digits 8 are victims of judicial system - wrongfully convicted for crimes they didn't commit. Luckily, most of them have been already released from the prison (i.e., there are more digits 8 outside the cages than inside the cages).
Civilians: Digits 2, 3 and 7 are law-abiding citizens - they might appear in the prison, but only as visitors.
Cop / Police power:Cop power: The power of a single cop equlas the number of cops he stands shoulder to shoulder with (i.e., sees by a chess king's move).
Which cops are better: Overall in the grid the power of digits 1 equals the power of digits 9, however digits 1 have less cops with no power than digits 9.
Police power: The power of the police in the box is a sum of powers of cops in that box.
Prisoners / Visitors:Prisoners: If a digit 4, 5, 6 or 8 appears in the prison, it is considered a prisoner.
Visitors: If a digit 2, 3 or 7 appears in the prison, it is considered a visitor.
The number of visitors cannot be greater than the number of prisoners within a single prison, with one exception (i.e., there is only one prison where the number of visitors is greater than the number of prisoners).
The sum of digits of all visitors in all prisons where the number of prisoners equals the number of visitors is 15.
Additionally, each prison with the number of prisoners equal to the number of visitors has the same sum of digits as one other prison in the grid.
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Below is the example to help you understand the cop power and the police power principles:
- Little red number in the top-left corner of digits 1 and 9 represents their cop power.
- Little blue number in the bottom-right of the box represents a police power in that box.
- The number of robbers in the prison in the box equals the police power in that box.
If you liked this puzzle, I recommend trying out my other puzzles:
Symmetrical Fan
Night Club
Broken Flashlight in the Darkness
Blown Fuses in Electrical Installation
Important Hour on the Clock
Let Me Introduce Myself
Positive Symmetry
Pretty Odd Shaded Area <- Recommended for you!
Erica
Erica 2
Erica 3
It's What You Do in the Dark That Puts You in the Light
Erica 4
What Was the Sum Again?
(+5)-Yang
Solution code: First (1st) column of the grid from top to bottom.
Comments
yesterday, 13:36 by ParaNox
Very enjoyable puzzle, I just had some trouble understanding the rules, especially this one: "Additionally, each prison with the number of prisoners equal to the number of visitors has the same sum of digits as one another prison in the grid"
I first interpreted it as "The mentioned cages have to have the same sum" not as "They individually have to have the same sum as one other cage (that does not fit the description given)".
Maybe "one other" instead of "one another" would be a better wording.
Otherwise, as I said, very enjoyable, thanks for this creative puzzle. :)
SK: Thank you for the comment! I have amended wording accordingly :-)
on 4. December 2025, 02:49 by Jastucreudo
It was really fun even with a unique and long ruleset to remember
on 2. December 2025, 09:49 by WvdWest
Wow, it took me longer to fully understand the ruleset than actually solving the puzzle. But very nice ruleset. Well done.
on 6. November 2025, 17:17 by StanleySudokunitz
While the hardest part may be understanding the rules (at least for me), the funnest part is also how creative they are!
on 23. October 2025, 17:45 by SennyK
Thank you very much for comments!
I was very proud of making this ruleset work, however I can tell by the number of solves that most of solvers give up after reading a new long ruleset. I think though that with the example given it is really approachable and also fun to solve with the story. I would love to see the rating on this one, which was my favourite until today, when I have published "Blown Fuses in Electrical Installation" :D
on 23. October 2025, 17:32 by abihummel
Really fun yet approachable ruleset! Most of the challenge of the puzzle is fully understanding and remembering all the rules. :D
on 21. October 2025, 18:36 by fredchen
Amazing puzzel with an astonishing ruleset.
It took a while for me to wrap my head around the rules but I really liked the logic and enjoyed solving it
