Given day, month, and year, this function finds the corresponding day of week. The days of week are encoded as the follows: Let's calculate the number of days passed since some Sunday modulo seven. For example, 31 December 2000 was Sunday.
In the previous article, I used DAWGs (called ternary DAGs in that article) for fuzzy search of misspelled words in a spell checker. A similar data structure can help to find words by their prefix, which can be mistyped, and sort them by fr…
There were sophisticated third-party applications for Windows Mobile 6: Why there are no such things for Windows Phone 7? Because Microsoft disallows native-code applications on this platform. Everything should be written in C# (or VB .NET)…
Filenames often contain numbers, e.g., picture17.png. If you apply the usual string comparison, two-digit numbers will be mixed with one-digit numbers: The “natural” order for alphanumeric data would be: Windows Explorer and other file mana…
The simplest way to implement a resizeable array in C is calling realloc each time you need to add a new item. However, this method is slow, especially under Windows. To reduce the number of realloc calls, you should allocate memory in chun…
In past, there was a clear difference between compiled languages and interpreted languages. The former were statically typed, often had manual memory management and powerful optimizing compilers (C, Pascal, Ada). The later were dynamically
Recent Intel processors (Core i7/i5) can calculate CRC-32C and bit count in hardware. With other domain-specific instructions (string handling, AES encryption) in SSE 4.2, it may seem that low-level optimization for these algorithms will so…
Three years ago, Steve Yegge published an article titled The Next Big Language. He described a language of future as: Most commenters guessed he talked about JavaScript (with GUI being Dynamic HTML). Programming tools are still immature, es…
This article summarizes tips and techniques for creating a good API or a software interface, i.e. the set of public classes and functions that connects the modules of your program. Win32 API, PHP standard library, and C run-time library wil…
What programming language should be learned first? And what was your first programming language? What are the criteria for choosing the first programming language? What language would you use if you wanted to teach programming to your kid?
You can often avoid repeating code by placing distinct parts of it into an array: The second version is not only smaller, but also more abstract and hence easier to maintain. To implement short command names, you have to modify the code in
Besides the technique of unrolling the loop and thus introducing performance boost for strlen function explained in Optimized strlen function it is also possible to go a little bit further and try to optimise strlen with SSE2 SIMD instructi…