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What are the barriers to understanding pointers and what can be done to overcome them? [closed]
... this:
type
THouse = class
private
FName : array[0..9] of Char;
public
constructor Create(name: PChar);
end;
When you initialize the house object, the name given to the constructor is copied into the private field FName. There is a reason it is defined as a fixed-s...
Fastest way to list all primes below N
...4.0 |
| sundaram3 | 416.0 |
+---------------------+-------+
Of all the methods tested, allowing numpy, for n=1000000,
primesfrom2to was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| primesfrom2to | 15.9 |
| p...
How can I define a composite primary key in SQL?
...for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from th...
How to duplicate a whole line in Vim?
...hen you press : in visual mode, it is transformed to '<,'> so it pre-selects the line range the visual selection spanned over. So, in visual mode, :t0 will copy the lines at the beginning.
– Benoit
Jun 30 '12 at 14:17
...
What does “#define _GNU_SOURCE” imply?
...
For exact details on what are all enabled by _GNU_SOURCE, documentation can help.
From the GNU documentation:
Macro: _GNU_SOURCE
If you define this macro, everything is included: ISO C89, ISO C99, POSIX.1, POSIX.2, BSD, SVID, X/Open, LFS, and ...
input type=file show only button
...
<input type="file" id="selectedFile" style="display: none;" />
<input type="button" value="Browse..." onclick="document.getElementById('selectedFile').click();" />
This will surely work i have used it in my projects.I hope this helps :)
...
Best TCP port number range for internal applications [closed]
...
Short answer: use an unassigned user port
Over achiever's answer - Select and deploy a resource discovery solution. Have the server select a private port dynamically. Have the clients use resource discovery.
The risk that that a server will fail because the port it wants to listen on is n...
Creating the Singleton design pattern in PHP5
...
/**
* Singleton class
*
*/
final class UserFactory
{
/**
* Call this method to get singleton
*
* @return UserFactory
*/
public static function Instance()
{
static $inst = null;
if ($inst === null) {
$inst = new UserFactory();
...
Bundling data files with PyInstaller (--onefile)
I'm trying to build a one-file EXE with PyInstaller which is to include an image and an icon. I cannot for the life of me get it to work with --onefile .
...
What is the advantage of GCC's __builtin_expect in if else statements?
...
I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...