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Can You Do the Regular Expression Crossword?
mikejuk writes "Programmers often say that regular expressions are fun ... but now they can be a whole lot of fun in a completely new way. Want to try your hand at a regular expression crossword? The idea is simple enough — create a crossword style puzzle with regular expressions are the 'clues.' In case you don't know what a regular expression is — it is a way of specifying what characters are allowed using wild-card characters and more. For example a dot matches any single character, an * any number of characters and so on. The regular expression crossword is more a sort of Sudoku puzzle than crossword however because the clues determine the pattern that the entries in a row have to satisfy. It also has to use a hexagonal grid to provide three regular expressions to control each entry. This particular regular expression crossword(pdf) was part of this year's MIT Mystery Hunt. This annual event is crammed with a collection of very difficult problems and the regular expression crossword, created by Dan Gulotta from an idea by Palmer Mebane, was just a small part of the whole — and yes there is a solution."
I think you mean .*
It's a great idea, but the puzzle given is too complicated.
If they really want to popularize this concept among programmers, many of whom have forgotten regular expressions even if they had once mastered them, they should really create much simpler puzzles in a mounting order of difficulty.
Hopefully, someone enthused by the idea will create and publish such puzzles.
There's probably already a CPAN module for solving it...
Solved it a few days ago. It was fun. It's not as hard as it looks.
and yes there is a solution
In fact, there is exactly one solution.
The article summary was wrong about * and so are you. At least the language in the summary leaves much to be desired, although they are correct about it being a numerator, they leave off the part that it matches the previous character or subexpression. * = the previous character or subexpression zero or more times. As Stradenko pointed out to get ANY character you need . (period). To get any character zero or more times you need .* (period asterix). To get the solution to anything with more than one line you need [\s\S]*.
So you're pretty far off the mark as far as 42 goes.
Yvonne Lee, Community Manager at Dice.com writes,
Python coder | PyQt Applications | Writer
No need to print out the puzzle, somebody made an interactive version:
http://twoevils.net/cross-regex.html
Randall should draw a comic about obligatory xkcd references.
Everywhere ^ is used in the puzzle it means that it matches anything not in the group. For example [^abc] would match any character except a, b and c
c++;