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Why does the C++ STL not provide any “tree” containers?
...a tree:
You want to mirror the problem using a tree-like structure:
For this we have boost graph library
Or you want a container that has tree like access characteristics
For this we have
std::map (and std::multimap)
std::set (and std::multiset)
Basically the characteristics of these two conta...
What's the best way to parse command line arguments? [closed]
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This answer suggests optparse which is appropriate for older Python versions. For Python 2.7 and above, argparse replaces optparse. See this answer for more information.
As other people pointed out, you are better off going wi...
JavaScript: How to find out if the user browser is Chrome?
I need some function returning a boolean value to check if the browser is Chrome .
13 Answers
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What is the difference between 'E', 'T', and '?' for Java generics?
I come across Java code like this:
6 Answers
6
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Best way to represent a fraction in Java?
...never overflow.. anyway, use it if you want it. I've been dying to show this off somehow. :)
Edit: Latest and greatest version of this code, including unit tests is now hosted on GitHub and also available via Maven Central. I'm leaving my original code here so that this answer isn't just a link......
How can I know if a process is running?
...a reference to a System.Diagnostics.Process , how can I know if a process is currently running?
13 Answers
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Checking network connection
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Perhaps you could use something like this:
import urllib2
def internet_on():
try:
urllib2.urlopen('http://216.58.192.142', timeout=1)
return True
except urllib2.URLError as err:
return False
Currently, 216.58.192.142 is one of ...
How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throw
I'm trying to upload a file using PrimeFaces, but the fileUploadListener method isn't being invoked after the upload finishes.
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How to avoid isset() and empty()
I have several older applications that throw a lot of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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When should I use the Visitor Design Pattern? [closed]
I keep seeing references to the visitor pattern in blogs but I've got to admit, I just don't get it. I read the wikipedia article for the pattern and I understand its mechanics but I'm still confused as to when I'd use it.
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