wu :: forums (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi)
riddles >> easy >> Xword Clues
(Message started by: Noke Lieu on Jan 21st, 2010, 6:30pm)

Title: Xword Clues
Post by Noke Lieu on Jan 21st, 2010, 6:30pm
So, a crossword puzzle (following the usual rules of layout), that's n x n squares...

what can you say about the number of clues?

What if the cross word was (n x m) ?

(sorry, a slow start to the year...  :'( )

Title: Re: Xword Clues
Post by Ronno on Jan 21st, 2010, 7:58pm
The minimum number of clues is probably Floor[(n+1)/2]*Floor[(m+1)/2]

The maximum depends on certain constraints, such as:
1. How short words are allowed?
2. Can the crossword be divided into separate sub-crosswords?

Title: Re: Xword Clues
Post by Noke Lieu on Jan 23rd, 2010, 7:28pm
Nice, but I was thinking of something much more pedestrian... (and now filled with a sense of uncertainty thinking through 2x2 a bit more openly...)


Title: Re: Xword Clues
Post by Noke Lieu on Jan 24th, 2010, 10:55pm
I was originally thinking that the crossword requires 4 fold rotational symmetry.

Title: Re: Xword Clues
Post by towr on Jan 25th, 2010, 1:43am
I've seen enough crosswords that aren't in any way symmetric.

Title: Re: Xword Clues
Post by Grimbal on Jan 25th, 2010, 8:00am
Around here (Geneva, french-speaking) they are never symmetric.

It seems to me UK or US crosswords tend to be symmetric.  I guess building crosswords is more difficult in some languages, making it too troublesome to make them symmetric.

Title: Re: Xword Clues
Post by rmsgrey on Jan 26th, 2010, 4:30am
As long as both n and m are greater than 1, there are at least two clues.

Assuming answers must be at least 3 letters, and that black squares separate answers, there's an upper bound of (m+1)n/4+m(n+1)/4 - if you add an extra column of black squares to the right of the grid, each across answer uses at least 4 squares - 3 letters and a black square - and similarly for down answers.



Powered by YaBB 1 Gold - SP 1.4!
Forum software copyright © 2000-2004 Yet another Bulletin Board