Logic Masters Deutschland e.V.

Obvious Killer II: everything looks wrogn

(Eingestellt am 8. April 2021, 14:10 Uhr von filuta)

This puzzle is a sequel to my previous puzzle with the same ruleset. The first one is (I think) very hard, but this one should be much easier (I hope). In a sense it is also a kind of tutorial for this ruleset.

A cage is an orthogonally connected region without repeats. A cage of size N is called obvious, if it sums to a number that can be expressed in only one way using N numbers 1-9 without repeats.

Rules of the puzzle: Standard sudoku rules apply. In addition, all possible 2,3 or 4-cell obvious cages that can be drawn in the finished solution are given as clues (i.e. there is a negative constraint on obvious cages) in the following sense:

every obvious cage of size 2, 3 or 4 that appears in the finished solution is either:
1) drawn in the grid (drawn clue), or
2) represented by its total written by a small number in the upper left corner of one of its cells (total clue).

The cages may intersect. Each total clue represents exactly one obvious cage. Each cage is represented by exactly one clue.

Have fun and thanks (in advance) for any feedback/comments!

f-puzzles link

Lösungscode: column 4 and row 5 (without a comma or a space)

Zuletzt geändert am 8. April 2021, 14:46 Uhr

Gelöst von NikolaZ, teddySMI, rimodech, Gramor, zorant, Tilberg, Kafkapharnaum, Prutsbeest, StefanSch, SudokuExplorer
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Zuletzt geändert am 3. September 2021, 13:42 Uhr

am 2. September 2021, 13:43 Uhr von StefanSch
The difficulty of understanding the rules is more than 2 stars. But then it's a real fun with many nice logic steps.
oh, thank you, yeah, I must say, I always thought of this ruleset as very intuitive, but really struggled to find any simple description of it.

Zuletzt geändert am 18. August 2021, 19:37 Uhr

am 18. August 2021, 17:26 Uhr von Prutsbeest
For some reason I find your puzzles to be extremely hard.. maybe it's because of the many different rules. In this case, I forgot about the negative constraint for a while which made things a lot harder :)
Anyway, very original set of rules, I enjoyed it!
Thank you once more, yeah, thats the problem with this ruleset, I just hope, the puzzles make up for it. The real deal is the original Obvios Killer though (so I hope you will try that one too - no preassure ofc).

Zuletzt geändert am 23. Juli 2021, 11:29 Uhr

am 23. Juli 2021, 10:24 Uhr von cdwg2000

I don't understand the rule set, if it is convenient, can you give a simple sample? Thanks!
So for example three orthogonally connected cells containing 124 would make an obvious cage, since they sum up to 7 and 7 can be expressed in only one way using three digits (without repeats). On ths other hand, three orthogonally connected cells containing 135 would not make an obvious cage, since they add up to 8 and 8 can also be expressed as 125. Similarly, 9875 would again make up an obvious cage, whereas 9874 wouldn't.

There is a negative constraint on obvious cages of sizes 2,3 and 4. This means that if the finished solution contains orthogonally connected cells containing 124, then there must be either a dashed line around those cells, or there must be their total indicated by a small number written in one of the cells (can be any of them). The point is that every obvious cage must be indicated, so for the run of digits 124, the triple 124 is an obvious cage but also 12 is an obvious cage and must have its own clue. Moreover, no two cages may share a clue, even if two 12 cages intersect, they cannot be represented by only one clue.

Here are some clumps of digits:

and here are some possible ways in which they can be represented:

I hope it's more understandable now.

Zuletzt geändert am 26. Juni 2021, 02:08 Uhr

am 25. Juni 2021, 19:13 Uhr von Kafkapharnaum
Wow, I kept entering row 4, column 5 and I was losing my mind there, "WHERE did I mess up!?" lol
But hey, I got this one down of the two at least! It's certainly a lot more manageable to only have to deal with the lower end of the obvious totals, so again, you did an excellent job constructing it. Impressive work again, congrats!

filuta: yeah, I remember after solving your Gradius which was my by far hardest solved puzzle at that time I was so excited it took me like three or four tries to get the code right lol,

but seriously, thank you so much for continuing the tour through my puzzles and for the comment
My pleasure! I really like how unique they all are, and I'm pleased to see that they seem to be getting more attention these days, including a solve and praise from the great zhergan I see! :D

Zuletzt geändert am 13. April 2021, 08:14 Uhr

am 12. April 2021, 17:41 Uhr von Gramor
I quite enjoy these obvious cages. Another really nice puzzle, thank you very much.

filuta: I'm glad you liked it. Thank you for your comment.

am 8. April 2021, 14:46 Uhr von filuta
fixed typo

Gelöst:10 mal
Beobachtet:3 mal


Lösung abgeben