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When should I use the HashSet type?
...sh what its members are, and to check whether an item is a member.
Asking if you can retrieve a single element (e.g. set[45]) is misunderstanding the concept of the set. There's no such thing as the 45th element of a set. Items in a set have no ordering. The sets {1, 2, 3} and {2, 3, 1} are iden...
What is an NP-complete in computer science?
..."choice" function). Basically, a solution has to be testable in poly time. If that's the case, and a known NP problem can be solved using the given problem with modified input (an NP problem can be reduced to the given problem) then the problem is NP complete.
The main thing to take away from an NP...
No output to console from a WPF application?
...o; }
}
/// <summary>
/// Creates a new console instance if the process is not attached to a console already.
/// </summary>
public static void Show()
{
//#if DEBUG
if (!HasConsole)
{
AllocConsole();
InvalidateOutAnd...
Bash if statement with multiple conditions throws an error
...ion. So your script would be like this:
my_error_flag=1
my_error_flag_o=1
if [ $my_error_flag -eq 1 ] || [ $my_error_flag_o -eq 2 ] || ([ $my_error_flag -eq 1 ] && [ $my_error_flag_o -eq 2 ]); then
echo "$my_error_flag"
else
echo "no flag"
fi
Although in your case you can disca...
How can I convert a string to boolean in JavaScript?
...esn't make any implicit type conversions when the compared variables have different types, instead of the equality operator (==).
var isTrueSet = (myValue === 'true');
Don't:
You should probably be cautious about using these two methods for your specific needs:
var myBool = Boolean("false"); ...
Javascript - removing undefined fields from an object [duplicate]
...key] === undefined && delete obj[key])
jsbin
Same example using if expression:
Object.keys(obj).forEach(key => {
if (obj[key] === undefined) {
delete obj[key];
}
});
If you want to remove the items from nested objects as well, you can use a recursive function:
const removeE...
How do I restart nginx only after the configuration test was successful on Ubuntu?
...I know, nginx would show an empty message and it wouldn't actually restart if the configuration is bad.
The only way to screw it up is by doing an nginx stop and then start again. It would succeed to stop, but fail to start.
...
Using ThreadPool.QueueUserWorkItem in ASP.NET in a high traffic scenario
...hread pool used for QueueUserWorkItem is also used to serve requests.
But if you are actually queuing enough work items to cause this starvation, then you should be starving the thread pool! If you are running literally hundreds of CPU-intensive operations at the same time, what good would it do t...
How do I change the text of a span element using JavaScript?
If I have a span , say:
13 Answers
13
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jQuery UI - Close Dialog When Clicked Outside
I have a jQuery UI Dialog that gets displayed when specific elements are clicked. I would like to close the dialog if a click occurs anywhere other than on those triggering elements or the dialog itself.
...