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When do I really need to use atomic instead of bool? [duplicate]
Isn't atomic<bool> redundant because bool is atomic by nature? I don't think it's possible to have a partially modified bool value. When do I really need to use atomic<bool> instead of bool ?
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How to elegantly deal with timezones
I have a website that is hosted in a different timezone than the users using the application. In addition to this, users can have a specific timezone. I was wondering how other SO users and applications approach this? The most obvious part is that inside the DB, date/times are stored in UTC. When on...
Where can I get a “useful” C++ binary search algorithm?
I need a binary search algorithm that is compatible with the C++ STL containers, something like std::binary_search in the standard library's <algorithm> header, but I need it to return the iterator that points at the result, not a simple boolean telling me if the element exists.
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Bash history without line numbers
The bash history command is very cool. I understand why it shows the line numbers, but is there a way I can invoke the history command and suppress the line numbers?
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Determine which element the mouse pointer is on top of in JavaScript
I want a function that tells me which element the mouse cursor is over.
13 Answers
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clearing a char array c
...ng the array as a series of chars, then the only way to clear out the data is to touch every entry. memset is probably the most effective way to achieve this.
On the other hand, if you are choosing to view this as a C/C++ null terminated string, setting the first byte to 0 will effectively clear th...
How do you crash a JVM?
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The closest thing to a single "answer" is System.exit() which terminates the JVM immediately without proper cleanup. But apart from that, native code and resource exhaustion are the most likely answers. Alternatively you can go looking on Sun's bug tracker for bug...
Determine the line of code that causes a segmentation fault?
How does one determine where the mistake is in the code that causes a segmentation fault ?
6 Answers
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How can I quantify difference between two images?
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General idea
Option 1: Load both images as arrays (scipy.misc.imread) and calculate an element-wise (pixel-by-pixel) difference. Calculate the norm of the difference.
Option 2: Load both images. Calculate some feature vector for each of them (like a histogram). Calculate distance b...
SQL SELECT speed int vs varchar
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Int comparisons are faster than varchar comparisons, for the simple fact that ints take up much less space than varchars.
This holds true both for unindexed and indexed access. The fastest way to go is an indexed int column.
As I s...