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Initializing a list to a known number of elements in Python [duplicate]
...at there are other legitimate cases than optimizations for the wish to pre-allocate an array. It could be the code that uses it doesn't add elements, just replaces existing ones, so it's more like an array than a list.
– Lasse V. Karlsen
Sep 10 '09 at 8:08
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Will code in a Finally statement fire if I return a value in a Try block?
...t. Thus, the only place a CER should be relevant is for resources that are allocated outside of the process, e.g., unmanaged handles.
Typically, unmanaged code is wrapped by some managed class before being consumed by user code. The managed wrapper class will typically make use of a SafeHandle to w...
Is GridFS fast and reliable enough for production?
... since it's up and running. The resize and store stuff is done by a simple php script... but for sure, a python script, or something like java could be faster.
Current data size : 11.23g
Current storage size : 12.5g
Indices : 5
Index size : 849.65m
About the reliability : This is very reliable....
Generate an integer that is not among four billion given ones
...
For the 1 GB RAM variant you can use a bit vector. You need to allocate 4 billion bits == 500 MB byte array. For each number you read from the input, set the corresponding bit to '1'. Once you done, iterate over the bits, find the first one that is still '0'. Its index is the answer.
...
recursion versus iteration
...w the return back to the caller functions. In many cases, memory has to be allocated and copied to implement scope isolation.
Some optimizations, like tail call optimization, make recursions faster but aren't always possible, and aren't implemented in all languages.
The main reasons to use recursi...
vim, switching between files rapidly using vanilla Vim (no plugins)
....html normal! mH
autocmd BufLeave *.js normal! mJ
autocmd BufLeave *.php normal! mP
augroup END
I recently found this gem in someone else's ~/.vimrc. It creates a file mark at the exact position of the cursor whenever you leave a buffer so that, wherever you are, 'J jumps to the latest Java...
Why should I prefer to use member initialization lists?
...le, but imagine if you will that A's default constructor did more, such as allocating memory or opening files. You wouldn't want to do that unnecessarily.
Furthermore, if a class doesn't have a default constructor, or you have a const member variable, you must use an initializer list:
class A
{
p...
Implementing IDisposable correctly
...enting IDisposable, you are announcing that
// instances of this type allocate scarce resources.
public class MyResource: IDisposable
{
// Pointer to an external unmanaged resource.
private IntPtr handle;
// Other managed resource this class uses.
priv...
Can I write into the console in a unit test? If yes, why doesn't the console window open?
...y open a console window, using P/Invoke as sinni800 says. From reading the AllocConsole documentation, it appears that the function will reset stdin and stdout handles to point to the new console window. (I'm not 100% sure about that; it seems kind of wrong to me if I've already redirected stdout fo...
system(“pause”); - Why is it wrong?
...summary, it has to pause the programs execution and make a system call and allocate unnecessary resources when you could be using something as simple as cin.get(). People use System("PAUSE") because they want the program to wait until they hit enter to they can see their output. If you want a progra...