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Regex Crossword

regexcrossword.com

91–100 of 115 posts

Re: Regex Crossword

#91
post #46
post #39

Earlier quoted context omitted.

The "I" can't be "T" because the regex on the bottom (.(\sSAI).*) forces it to be "I".

No in this case the regex on the bottom only applies the . to the square in question while the \sSAI in question applies to the second square. It seems that it could be a I or a T.

(\sSAI) is a group, not a character class. It matches the fixed string " SAI" and stores it in a group. If it were [\sSAI], you'd be correct.

Re: Regex Crossword

#92

These crosswords are NP-hard! D: Here's a short encoding of 3SAT: Alphabet: [01] Number of variables: N Columns: one for each clause, i.e.: r/.0...|..1..|....1/ (-x2 V x3 V x5) They're disjunctions of three regexps of length N. Each alternative fixes one positional variable to either 0 or 1, and ignores the rest. Rows: one for each variable, forcing it to be single-valued across the clauses: r/0+|1+/

Well, that sure cured me of the intuition that these square grid regexp crossword puzzles were inherently easier than the original hexagonal grid version!

Re: Regex Crossword

#93
post #45
post #41

Earlier quoted context omitted.

The MIT puzzle (from the 2013 Mystery Hunt) was called "A Regular Crossword" and its credit says "Dan Gulotta, based on an idea by Palmer Mebane". (Just so it's not credited to MIT in general; each year's Mystery Hunt is written by a specific puzzle team, and indeed each puzzle is written by specific puzzlers!)

This new site is super-awesome and challenging, but a great thing about the hexagonal grid in "A Regular Crossword" was that each hexagon was constrained by three intersecting regular expressions rather than two. That meant that the constraints could be trickier or vaguer in some ways, and comparatively more dependent on the sequence of elements within a regular expression rather than on the process of elimination be…

Elsewhere in this thread, a commenter points out that the square grid regular expression puzzle can encode 3SAT instances, so I was wrong to call these easier than the hexagonal version.

Re: Regex Crossword

#94
post #16

My main problem with this is telling the difference between O and 0, the clue O's look more like 0 so I have to copy paste them. (Although I don't think I've had any numbers required for solutions yet).

Came across same thing. I did: Cmd + F; "O".

Re: Regex Crossword

#96
I want to be able to return later, but it's a bit too much to register a Facebook account (which you presumably can't do with a throwaway address?).

I'd be happy to donate more than whatever Facebook pays you for every newly registered account if you would implement a simpler method.

Re: Regex Crossword

#97
post #96

I want to be able to return later, but it's a bit too much to register a Facebook account (which you presumably can't do with a throwaway address?). I'd be happy to donate more than whatever Facebook pays you for every newly registered account if you would implement a simpler method.

How is this too much? FB reg is the simplest way possible online to create an account anywhere.

Re: Regex Crossword

#98
post #96

I want to be able to return later, but it's a bit too much to register a Facebook account (which you presumably can't do with a throwaway address?). I'd be happy to donate more than whatever Facebook pays you for every newly registered account if you would implement a simpler method.

How is this too much? FB reg is the simplest way possible online to create an account anywhere.

There are lots of people who simply don't want to give anything to FB. You don't have to be one of them but you at least have to recognize them.

Re: Regex Crossword

#100

What does it mean when a reg ex ends with a `\1` (backslash 1) as in this example third beginner puzzle? (.)+\1 http://regexcrossword.com/challenges/beginner/puzzles/3

Speaking of that puzzle how come [COBRA]+ and (.)+\1 give back result 'O'? Why not C or B or A?
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