Hot & Cold: A Primer
(Published on 30. April 2024, 08:15 by ViKingPrime)
PUZZLE:
RULES:
Normal Sudoku rules apply.
• Arrow: Digits along an arrow must sum to the value in its originating circle.
MODIFIERS:
• Hot/Cold: There are 9 Hot cells contained within the grid comprising a set of the digits from 1-to-9. Each row, column and box contains exactly one Hot cell. There are nine 9 Cold cells contained within the grid following the same rules as the Hot cells. A cell may have only one of these roles.
for Arrow value(s)
Hot cells increase the value of the contained digit by 1.
Cold cells decrease the value of the contained digit by 1.
INTRODUCTION:
Presented in the style of Azireo's fabulous "9-Steps Tutorial" series.
This is a response to some of the comments from a previous puzzle, which while appreciative, described the constraint as "grinding the numbers". The nature of the logic might necessitate that a little, however I find it quite helpful to keep track of what remaining options there are in the grid for the Hot and Cold cells, as it's often quite more limited than it might appear at a glance.
The side cells are not necessary - you can solve the puzzle without pencilmarking them - but I suspect you'll find the solve more enjoyable with them included.
Here are some puzzles from other setters using the same constraint:
Hot and Cold by brennan77
Hot and Cold Cages by brennan77
Have fun!
Solve in SudokuMaker!
Solve in SudokuPad!
Solution code: The digits along Row 8, left-to-right.
Comments
on 21. May 2024, 03:06 by gdc
Very nicely constructed puzzle. I liked the "9-steps tutorial" reference.
About the track cells: I can just repeat what @SudokuHero said. Lovely addition, but the bottom two rows are redundant and shrink the grid.
on 12. May 2024, 19:02 by QuiltyAsCharged
It's an interesting exercise to use this as a primer, and to see in the comments the various perspectives on tracking one's progress. It's also just a great puzzle with some tricky deductions, but not overly difficult.
What works best for me is using three colors: red/blue for hot/cold, and grey for room temperature cells. When there are 2 or 3 candidates for hot or cold in a box, I mark them as half colored and half white. This makes it easy to scan the board for potential hot/cold locations.
The suggestion from VitP to use 4 colors is interesting, but for me that would be a little too noisy and unintuitive.
The bottom tracker cells were very helpful! I love being able to see at a glance which digits are still available for each temperature.
I tried to use the side tracker cells but I just didn't find them helpful. Between my coloring and the bottom tracker cells, I had all the information I needed.
on 3. May 2024, 19:39 by SudokuHero
Loved it. I also love the ability to track the digits, it made it so much easier to solve. The bottom space is a bit redundant though, you could make do with just the side digits.
on 3. May 2024, 17:11 by MartinR
Tricky in places, especially when hot and could could interact.
For the rules, they say "digits" on an arrow add to the "value" in the circle, should this not be values for both?
on 2. May 2024, 11:07 by ThePedallingPianist
What a neatly-constructed puzzle, and such a smart and generous idea to offer the solver such clear trackers! Every step is clearly signposted and fairly straightforward when you're looking in the right place, so even though a complex variant like this will almost never yield a 1-star difficulty puzzle, this is the best possible primer for Hot and Cold cells. I do hope these trackers become the standard for modifiers like this.
on 1. May 2024, 22:20 by VitP
i appreciate the extra effort you went to to help with the administrative details, but in these types of puzzles, i find it necessary to mark the ENTIRE grid with 4 distinct colours. eg. red/green for hot or not, and blue/yellow for cold or not.
on 30. April 2024, 18:04 by mihel111
Very nice puzzle, VP. And I agree with you concerning keeping track of hot/cold cells. The main gold is to give a maximum of people a maximum of joy. If it can help some, it's a good thing.
Thank you
