Listener 4451 Numerical Playfair By Zag

[midazolam]

Typical Zag, original concept. Not my cup of tea (but then numericals aren't), but appreciate the way it was constructed to an unambiguous gridfill.

[Cagey]

I enjoyed this. Nice combination of logic and maths. Not tackled a numerical listener in a while. i like the idea. Thank you zag.

[Ruthrobin]

I loathe numericals but actually enjoyed this one once we saw the way in (which did involve a bit of computing for the more mathematical other half) but all came together beautifully at the end. Thanks to Zag.

[Encota]

Given it includes the words 'numerical' and 'Playfair', I suspect this might frighten away more people than it should. An enjoyable puzzle - thanks Zag!

[word_cross]

How do we treat odd digit entries for playfair? Add a 9 on the end?

[word_cross]

Oh dear. Scratch that. I have now properly read the preamble

[olichant]

Boy, do you ever get punished by a numerical if you make a mistaken assumption early on! But I only have myself to blame for my idiocy. Enjoyed it in the end, and I'm always amazed at how such a parsimonious set of clues (and actually, I'm not sure I used quite all of them) leads to a unique result incorporating a variety of logical processes. Would love to see a setter's blog...

Thanks, Zag. I'll have to have a shot at the Magpie Zag numerical now...

[Contrarian]

My sentiments exactly Olichant.

I was close to throwing in the towel for a while.

[Oyler]

Very neat indeed and typical of Zag. For those interested the last time a Playfair code was used in a Listener mathematical was in 1993 - Alphanumerics by Piccadilly. I can still remember the code square to this day - how sad is that? You don't have to respond!!!

[AHearer]

A good thing it's a wet weekend, or I might have given up. As ever, admiration of the setter's skills in numericals. Many thanks, Zag.

[midgler]

Elegant and economical, much more logic than maths. Second the comment about a setter's blog, I'd be fascinated to understand the construction process.

[icynorth]

I agree this was elegant and challenging, thanks Zag!

Quick and easy to check, too!

[starwalker]

My dislike of numericals is well documented, but I kicked myself when I finished this. I'm still puzzled why it took me so long just to assemble the components that I had got much earlier. Easy checking for JEG this week.

[Oyler]

Olichant, midgler. You'll be pleased to know that Zag is indeed preparing a blog on this puzzle for LWO.

[s_pugh]

Like others I loathe numericals but thought I'd managed to crack this one after many hours of toil and lots of paper. Then right at the end I realised to my horror that I hadn't accounted for 2ac being the multiple of another entry. Boy was I glad when I found that it fortuitously was! Surely though this would be well nigh impossible without the assistance of spreadsheets, factor calculators etc?

[sunny-dave]

Similar mistake to s_pugh - in my case I made an assumption about the sub_multiple that made me throw away an otherwise virtually finished solution.

I then ground through a fresh attempt from first principles - to arrive at exactly the same grid and promptly realised that it was actually correct :(

As I've said before, when I first started The Listener about 20 years ago I welcomed numericals because I could actually do them ... now I cordially dislike them because of their 'unbacktrackability' (if it's not in the BRB then it should be) - starting from scratch each time you hit the wall gets tedious, but is unavoidable if you don't know where your dodgy logic is.

Thanks though to Zag - in the end an elegant puzzle that actually didn't need all the brute-force firepower that some from 'the other place' seem to have trained on it.

[icynorth]

I can't imagine how you would use a simple spreadsheet to solve this. You'd need some sort of procedural extension like VBA, and, frankly, life's too short for that. My squared paper and coloured pens did the job admirably.

[Philoctetes]

I enjoyed it, but would have liked the logical progression to continue a bit longer before I resorted to writing out all the possibilities and ticking them off. I always enjoy numericals, but they usually leave me feeling a little hollow - I haven't learnt anything new from my workout.

[BMACMAC]

I found this puzzle less arduous than some numericals, but couldn't avoid one abortive attempt following on from a miscalculation, which took me some time to pin-point. I found the final resolution, involving the Playfair code square quite interesting, and was relieved when everything fell into place. Thank you Zag.

[Liathach]

This took me a while and I made the mistake of abandoning on the final step before repeating the process and then realising that I had made an unwarranted assumption about the 3 digit entries. I am not sure what a previous poster means by 'More logic than maths' though. Maybe 'More maths than arithmetic'?

[borealis]

Liked this very much, but expected to find lots of complaints here. Glad you all seem to have enjoyed it, also. Like others, convinced myself I was wrong at the final step, and almost restarted, then managed it. Very nice that it was very do-able without brute force. Thanks, Zag!