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Java Hashmap: How to get key from value?
If I have the value "foo" , and a HashMap<String> ftw for which ftw.containsValue("foo") returns true , how can I get the corresponding key? Do I have to loop through the hashmap? What is the best way to do that?
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Python: fastest way to create a list of n lists
...None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edit: Using NumPy, you can avoid the Python loop using
d = numpy.empty((n, 0)).tolist()
but this is actually 2.5 times slower than the list comprehension.
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When should I use std::thread::detach?
... also know join() waits until a thread completes. This is easy to understand, but what's the difference between calling detach() and not calling it?
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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Send attachments with PHP Mail()?
...cript from here: http://github.com/PHPMailer/PHPMailer
Extract the archive and copy the script's folder to a convenient place in your project.
Include the main script file -- require_once('path/to/file/class.phpmailer.php');
Now, sending emails with attachments goes from being insanely difficult t...
Cannot import the keyfile 'blah.pfx' - error 'The keyfile may be password protected'
...ls\sn.exe. Most likely this location is not on the search path for your standard environment. However, the "Developer Command Prompt" installed by Visual Studio adds additional information that usually includes the correct location.
Based on your post that would look like
sn -i companyname.pfx V...
How do I unlock a SQLite database?
...//www.nirsoft.net/utils/opened_files_view.html to find out the process is handling db file. Try closed that program for unlock database
In Linux and macOS you can do something similar, for example, if your locked file is development.db:
$ fuser development.db
This command will show what proce...
How do I decode a string with escaped unicode?
... to http://example.com with JavaScript? I tried unescape , decodeURI , and decodeURIComponent so I guess the only thing left is string replace.
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Should I call Close() or Dispose() for stream objects?
... void Close()
{
this.Dispose(true);
GC.SuppressFinalize(this);
}
And StreamReader is:
public override void Close()
{
this.Dispose(true);
}
The Dispose(bool disposing) override in StreamReader is:
protected override void Dispose(bool disposing)
{
try
{
if ((this.Clos...
CSS3 gradient background set on body doesn't stretch but instead repeats?
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In Chrome and Safari, body { height: 100% } results in the page (but not the gradient) extending down out of the viewport.
– thSoft
Dec 17 '10 at 10:46
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