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Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
I have taken Problem #12 from Project Euler as a programming exercise and to compare my (surely not optimal) implementations in C, Python, Erlang and Haskell. In order to get some higher execution times, I search for the first triangle number with more than 1000 divisors instead of 500 as stated...
eval command in Bash and its typical uses
...guments, they are first joined with spaces between them.)
${$n} is a syntax error in bash. Inside the braces, you can only have a variable name, with some possible prefix and suffixes, but you can't have arbitrary bash syntax and in particular you can't use variable expansion. There is a way of say...
Is cout synchronized/thread-safe?
...t effect in that particular implementation) are guaranteed to be mutually exclusive, the buffer might be shared by the different threads. This will quickly lead to corruption of the internal state of the stream.
And even if access to the buffer is guaranteed to be thread-safe, what do you think wil...
Learning assembly [closed]
...bled code and maybe being able to write more efficient parts of code (for example, through c++), doing somethings like code caves, etc. I saw there are a zillion different flavors of assembly, so, for the purposes I mention, how should I start? What kind of assembly should I learn? I want to learn b...
git + LaTeX workflow
I'm writing a very long document in LaTeX. I have my work computer and my laptop, and I work on them both. I need to keep all the files synchronized between the two computers, and also would like to keep a revision history. I chose git as my DVCS, and I'm hosting my repository on my server. I'm also...
What's “wrong” with C++ wchar_t and wstrings? What are some alternatives to wide characters?
...se of wstrings and wchar_t , and their use in the windows api. What is exactly "wrong" with wchar_t and wstring , and if I want to support internationalization, what are some alternatives to wide characters?
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Is file append atomic in UNIX?
In general, what can we take for granted when we append to a file in UNIX from multiple processes? Is it possible to lose data (one process overwriting the other's changes)? Is it possible for data to get mangled? (For example, each process is appending one line per append to a log file, is it po...
Why does my application spend 24% of its life doing a null check?
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The tree is massive
By far the most expensive thing a processor ever does is not executing instructions, it is accessing memory. The execution core of a modern CPU is many times faster than the memory bus. A problem related to distance, the further an electrical...
How do you use bcrypt for hashing passwords in PHP?
...ash passwords. While the encryption phase of Eksblowfish and Blowfish are exactly the same, the key schedule phase of Eksblowfish ensures that any subsequent state depends on both salt and key (user password), and no state can be precomputed without the knowledge of both. Because of this key differe...
Why should I use core.autocrlf=true in Git?
I have a Git repository that is accessed from both Windows and OS X, and that I know already contains some files with CRLF line-endings. As far as I can tell, there are two ways to deal with this:
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