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What's “P=NP?”, and why is it such a famous question? [closed]
...ther P=NP is perhaps the most famous in all of Computer Science. What does it mean? And why is it so interesting?
6 Answers...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...n a low level language (C, C++ or whatever): I have the choice in between either having a bunch of mutexes (like what pthread gives me or whatever the native system library provides) or a single one for an object.
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Why does !{}[true] evaluate to true in JavaScript?
...cause plain {}[true] is parsed as an empty statement block (not an object literal) followed by an array containing true, which is true.
On the other hand, applying the ! operator makes the parser interpret {} as an object literal, so the following {}[true] becomes a member access that returns undef...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...o square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
There is a case where a map will be constructed, and once it is initialized, it will never be modified again. It will however, be accessed (via get(key) only) from multiple threads. Is it safe to use a java.util.HashMap in this way?
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C++ performance vs. Java/C#
...ding is that C/C++ produces native code to run on a particular machine architecture. Conversely, languages like Java and C# run on top of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this inte...
Why don't self-closing script elements work?
...nce of an element whose content model is not EMPTY (for example, an empty title or paragraph) do not use the minimized form (e.g. use <p> </p> and not <p />).
XHTML DTD specifies script elements as:
<!-- script statements, which may include CDATA sections -->
<!ELEMENT ...
Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...ementation which is coming in the imminent 2.8 release. Those familiar with the library from 2.7 will notice that the library, from a usage perspective, has changed little. For example...
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Visual Studio 2010 isn't building before a run when there are code changes
I've been using using F5 (Start Debugging) for years to build the code (if its out of date), and then debug. This was working on VS 2010 also, however today it just start debugging without a build. Say I do a clean on the project, and then hit F5 instead of building it so it can run it throws an err...
Differences between distribute, distutils, setuptools and distutils2?
...t updated" date displayed, so you can check the recency of the manual, and it's quite comprehensive. The fact that it's hosted on a subdomain of python.org of the Python Software Foundation just adds credence to it. The Project Summaries page is especially relevant here.
Summary of tools:
Here's a...