I’d just read a book called Introduction to the Theory of Computation by Michael Sipser and found it fascinating enough that I tried to encapsulate what NP-complete means in a 2000-word essay for October 2010’s issue. Was I successful? You’ll have to read it to find out. […]
READ MOREApologies to all if you saw a whole bunch of posts appearing and disappearing in the past hour. I’m having – all of a sudden – extreme problems with publishing a blog post from Windows Live Writer to this blog, which is hosted on GoDaddy. This first happened on November 5, but I thought it was a transient issue and ignored it. And then over the weekend I wrote the “adding parentheses” post but it would not publish, no matter what. I finally published it just now with Graffiti’s admin app, which is not nice. […]
READ MOREOnce upon a time (all right, it was in May 2010), I wrote an article for PCPlus about generating all possible arithmetic operations with the standard four operators. You can read the article here. After I’d written it, I wrote a blog post about how easy it was to convert the RPN form (Reverse Polish Notation) of the expressions I was generating into the standard algebraic or infix form. You can read that post here. (Note that this post will make more sense if you read these two articles first to get some background.) […]
READ MOREAh, memories, memories. For September 2010’s issue I wrote about how to solve Rubik’s Cube, and it allowed me to revisit my days at Kings’, London, when I first came across the puzzle. Back in those days (and probably even now), the Maths Society at Kings had a fun weekend away in Windsor Great Park where we’d have talks about recreational mathematics. (Yes, I know, many people don’t think “recreational” and “mathematics” can be in the same sentence, but bear with me here.) Of course, it was an occasion for too much drinking and smoking and playing 3-card brag and staying up all night, but in 1979 we discovered a puzzle that pushed all that aside: Rubik’s Cube. […]
READ MOREThis particular article explored how to generate arithmetic expressions using a card game as a basis for discussion. It appeared in August 2010, and came about because of me reading two blog posts on entirely different topics within a week or so of each other. The combination triggered an Ah ha! moment, and I wrote it up. The first was for a card game called Krypto and appeared on The Daily WTF; the second was about generating all binary trees of a particular size and appeared on Eric Lippert’s blog, Fabulous Adventures in Coding. […]
READ MOREWhile we were in England in September, we nipped over to see Long Meg and her daughters. […]
READ MOREAbout a month ago (I was at the DevLink conference), I heard about an iPhone app called 360 Panorama that takes panoramic pictures. The way it does it is quite intuitive once you realize that it takes a series of pictures and then stitches them together in software to produce a single JPG. […]
READ MOREThere are two types of sort algorithm: those that are stable and those that are not. Stable sorts maintain the order of items that are deemed equal, whereas unstable sorts make no such guarantees. […]
READ MOREI’ll admit this one is really wacky, so sit yourself down and read through this slowly. It’s OK if you need to take a break for a breather and to clear your mind. I had to the first time I came across this little, er, hack. […]
READ MORELike 99% of all jQuery users, I write the code I want executed when the document is ready like this: […]
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