Questions regarding WSC round 5 - Arrows, Lines and Circles

[Richard]

All questions regarding WSC round 5 must be asked here.

[rob]

5.10 Odd-Even Bridge Sudoku

I remember seeing this type without the restriction that the circles for each line are one odd/one even. Unfortunately the example doesn't help here because they are always in one line. I don't really expect you to make a new example here, but perhaps the extra rule could be emphasised typographically? (Or perhaps the competition puzzle has the same property, in which case of course it doesn't really matter much.)

[Richard]

I don't know if I understand your question right. Are the rules not clear enough? As far as I can read them, it's absolutely clear what must be done.

[Feadoor]

I agree that the rules are clearly stated. However, I believe Rob's point is that this variant has appeared on multiple other competitions without the extra stipulation that "Each connected pair of circles contains one even digit and one odd digit" - and I think he is asking for this sentence to appear in boldface or to be otherwise emphasised in the IB.

[rob]

Yes exactly.

"Normal" rules for the type allow both ends to be the same. Here there's the extra rule that both ends must be different.


This extra rule should ideally be shown in the example. That is, there (a) should be at least one bridge where the ends are in different rows and columns, and (b) the puzzle should have more than one solution without the extra rule.

Without such an example, it could easily happen to solvers who are familiar with the type that they miss this extra rule, and then run into the situation during the competition that the puzzle has multiple solutions.

However I understand that making examples is quite a bit of work, and you might not want to replace the example this shortly before the competition.


Thus the suggestion to put an emhasis on the extra rule, so that solvers are drawn to it, both while working through the example puzzle, and when rereading the instructions in the event of insecurity during the competition.

[Richard]

Yes exactly.

"Normal" rules for the type allow both ends to be the same. Here there's the extra rule that both ends must be different.


This extra rule should ideally be shown in the example. That is, there (a) should be at least one bridge where the ends are in different rows and columns, and (b) the puzzle should have more than one solution without the extra rule.

Without such an example, it could easily happen to solvers who are familiar with the type that they miss this extra rule, and then run into the situation during the competition that the puzzle has multiple solutions.

However I understand that making examples is quite a bit of work, and you might not want to replace the example this shortly before the competition.


Thus the suggestion to put an emhasis on the extra rule, so that solvers are drawn to it, both while working through the example puzzle, and when rereading the instructions in the event of insecurity during the competition.

We didn't even realize that this is other than 'the standard', and have looked to SVS231 (https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?chlang=en&id=0002SL).
In the whole IB there is no such emphasizing, but I don't have a problem with setting the sentence in Bold. I'll suggest that to Ulrich, who is doing all the graphics.

[rob]

We didn't even realize that this is other than 'the standard', and have looked to SVS231 (https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?chlang=en&id=0002SL).
In the whole IB there is no such emphasizing, but I don't have a problem with setting the sentence in Bold. I'll suggest that to Ulrich, who is doing all the graphics.

It's probably a good idea, thanks!

(The type has been on Sudoku GP and LMI at least without the rule, e.g. https://gp.worldpuzzle.org/content/compe...puzzles-32 or http://logicmastersindia.com/lmitests/dl...mentid=720 )

[Feadoor]

(The type has been on Sudoku GP and LMI at least without the rule, e.g. https://gp.worldpuzzle.org/content/compe...puzzles-32 or http://logicmastersindia.com/lmitests/dl...mentid=720 )

And, perhaps more to the point, on WSC 2017 where I believe the type appeared for the first time: http://logicmastersindia.com/lmitests/dl...tid=669&v1

[Fred76]

Hi,

I noticed while looking at the IB that you used a palindrome sudoku which I've created. It is not a WPF sudoku. You'll find it on my blog with reference to the competition in which it appears initially.
Can you add my name in the credit section in the next version of IB?

Thanks,
Fred

[Richard]

Hi,

I noticed while looking at the IB that you used a palindrome sudoku which I've created. It is not a WPF sudoku. You'll find it on my blog with reference to the competition in which it appears initially.
Can you add my name in the credit section in the next version of IB?

Thanks,
Fred

We took this example from the Instruction Booklet of the Dutch Grand Prix Round in 2016 (and maybe it's used more often, I don't know; we started with our own rounds), so we believed it is a WPF-puzzle.