This article discusses the use of C++ hash containers to improve storage of subproblem results when using dynamic programming (DP.) Memoization is a key part of dynamic programming, which is conventionally done by storing subproblem results in simple tables or lists. Using hash tables instead of these simpler structures will allow you to use dynamic programming while retaining your algorithm’s natural recursive structure, simplifying design and making your code easier to follow. I’ll provide a fully-developed example of an algorithm, and show how it can be adapted to use hash table memoization.

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It seems like this is the summer of multicore panic. I can’t open a technical magazine without some pundit declaring that our current programming paradigms are useless when running on new multicore CPU architectures. Venerable analyst John Dvorak, who generally actually understands what he is writing about, coughed up this mess (with minor excisions for [...]

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My email address shows up in a lot of public places, including domain registration records, hundreds of USENET posts, magazine articles, and various web sites. As a result, it has been harvested by every spammer known to mankind, and I get a lot of bad email. This includes more than just spam. I show up [...]

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This article presents the algorithm that solves the Byzantine General’s Problem, as first described by Lamport, Pease, and Shostak in 1982 [1]. While Lamport’s algorithm is not particularly complex, programmers who aren’t used to working on distributed computation might find it difficult to implement. To accompany the explanation of the algorithm, I have included a C++ program designed for experimentation with the solution.

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The IEEE has announced its list of medal winners for 2007, and this year’s Richard Hamming medal was awarded to Dr. Abraham Lempel: For pioneering work in data compression especially the Lempel-Ziv algorithm. This is a timely award, because it comes on the 30th anniversary of the publication of the first of two seminal papers [...]

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With the tight security at our nation’s airports, it’s kind of surprising to see a security warning from Windows show up on the Anchorage airport’s flight status screens!

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Dr. Dobb's PortalApril, 2007 Article on DDJ site I'm an inveterate fan of wordplay of all sorts - puzzles, anagrams, crosswords. I've been known online by my anagrammatic name, SnorkelMan, all the way back to the ancient days of the text mode BBS. My continual hectoring of the staff at the Dallas Morning News over [...]

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