A recent xkcd cartoon has started some deep academic thinking. When AI expert Peter Norvig gets involved you know the algorithms are going to fly. Xkcd is our favourite comic and regular expression are definitely our favourite way to spend the time waiting for the next installment - so what could be better than an xkcd cartoon on Regex Golf. Code Golf is a reasonably well known sport of trying to code an algorithm in the shortest possible code. Regex Golf is similar, but in general the aim is to create a regular expression that accepts the strings in one list and rejects the strings in a second list. This should have been enough, but clearly we are programmers and we like recursion and a regex is a string after all and a regex can process a string: Yes my friend, it's regexes all the way down! Mind boggling enough, but the hover over text, a key feature of many xkcd funnies, is where the problem really starts to take off and gain a life of its own. The text gives a regular expression that matches the last names of the elected US presidents, but not the losers.
This started Peter Norvig, the well-known computer scientist, director of research at Google and wearer of brightly colored shirts, thinking about the problem. Is it possible to write a program that would create a regular expression to solve the xkcd problem? The problem is one level of meta, i.e. it is a program that creates a regular expression, but it is a difficult one that needs AI-like search techniques. The basic algorithm is to first derive a pool of regexs for short character sequences in the data that match a least one winner but no losers. Then create a bigger regex by or-ing a selection of components together. Vary the selection until you get a regex that matches all of the winners but none of the losers. This is equivalent to the set cover problem and hence NP hard. To try to find the smallest regex that does the job the simplest approximate way is to use a greedy selection that picks component regexs that maximally separate the two lists first. From here the algorithm can be improved by adding a set of rules for generating the initial pool of regexs.
To find out more read the complete description, including Python code, at Peter Norvig's blog post which ends with the challenge: "I hope you found this interesting, and perhaps you can find ways to improve my algorithm, or more interesting lists to apply it to. I found it was fun to play with, and I hope this page gives you an idea of how to address problems like this." Or, of course, you could take the problem to one stage more of meta e.g meta-meta-regexgolf - a program that writes programs that writes regexs.... If you would like to play more Regex Golf, with or without the help of a program, visit: http://regex.alf.nu/Estás en: Inicio > Acerca de la ENP > Directorio de Dirección General Adolfo Prieto No. 722 Col. Del Valle C.P. 03100 Ver UNAM Dirección General de la Escuela Nacional Preparatoria en un mapa más grande Hecho en México, todos los derechos reservados 1998-2011. Esta página puede ser reproducida con fines no lucrativos,
siempre y cuando no se mutile, se cite la fuente completa y su dirección electrónica. De otra forma requiere permiso previo por escrito de la institución. eBay Search Results for NEW Lego CLASSIC TOWN 6481 Construction Crew Sealed LEGOLAND Lego Town 9V Electric Light System 6481 Construction Crew NEW SEALED LEGOLAND Lego Vintage Light System Set #6481, Construction Crew, Was Produced In 1989 vintage LEGO legoland 6481 6361 6603 6671 Construction crew shovels with manuals LEGO INSTRUCTION BOOKLETS 6897 16281480 1969 6521 6661 6358 6481 6480 6828! What is your return policy? How do I check my gift card balance? Don't see your question? Visit our help section. See all best sellers Five Nights at Freddy's Drones & High-Tech Gadgets The Legend of Zelda Movie & TV Stuff See All Cool Stuff XBOX One Digital Content Xbox Digital Gift Cards Shop XBOX One by ESRB See All XBOX One Shop PS4 by ESRB
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Yup, from the looks of it, we might well be set to see not one Ant-Man, but two.This newly revealed (and conspicuously awesome) Lego set, first seen at this weekend's New York Toy Fair... Which, sure, features Paul Rudd's Ant-Man... And Corey Stoll's Villainous Yellowjacket... And even a giant ant... But y'know what it also features? A whole other Ant-Man... And, from the looks of it, that's none other than Hank Pym himself - the original comic-book Ant-Man, set to be played in the movie by Michael Douglas. Which, it would seem, suggests we're set to see Douglas' Pym suit up in the movie, and battle crime alongside his new protegee. Which, seeing as a whole lot of fan-concern surrounding Ant-Man has been focused on the movie's apparent jettisoning of the character's original comic-book roots, could well be a very good thing.Could we even get the chance to see Pym don the suit in flashbacks - perhaps even alongside the original Wasp, Janet van Dyne?Here's hoping - but whatever else happens, it certainly now looks as though we're set to see Pym don his own version of the Ant-Man suit and join the fight.
Which means Michael Douglas just officially became a superhero.Y'know, that, or Lego didn't want to make a Michael Douglas mini-figure if he wasn't wearing a super-suit. I'm totally down either way...What do you guys think, though? Will we actually see the original Wasp in the movie? Will Michael Douglas really Ant-Man-suit up? Just how good do you think Ant-Man will be?via IGN What Ever Happened To Viral Star Chris Crocker? His Fame-Fueled Life After 'Leave Britney Alone!' Happily Never After: This Fan Art Reveals the Darker Sides to the Stories That Inspired Disney Classics Kick Off 2017 With These Great Horror Films On Netflix! IMDb May Have Leaked Spider-Man PS4's Villain...And He Has A Very Familiar Face Coach Invites Ronda Rousey to Train With 'Cyborg' Justino Miss Sinister Is a Super Talented Cosplayer: Take a Look at Her Incredibly Diverse Portfolio Chris Pine Reportedly Closes Deal to Play Steve Trevor in 'Wonder Woman' Billions Episode 7 Review The Punch