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Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...
Row count with PDO
... question, the only reason mysql_num_rows() worked is because it was internally fetching all the rows to give you that information, even if it didn't seem like it to you.
So in PDO, your options are:
Use PDO's fetchAll() function to fetch all the rows into an array, then use count() on it.
Do an ex...
Code Golf: Collatz Conjecture
...sp+0x04], 2
jne .usage
mov ebx, [esp+0x08]
push dword [ebx+0x04]
call atoi
add esp, 4
cmp eax, 0
je .usage
mov ebx, eax
push eax
push msg
.loop:
mov [esp+0x04], ebx
call printf
test ebx, 0x01
jz .even
.odd:
lea ebx, [1+ebx*2+ebx]
jmp .loop
.even:
shr ebx, 1
...
What is time_t ultimately a typedef to?
...IX-compliant systems implement the time_t type as a signed
integer (typically 32 or 64 bits wide)
which represents the number of seconds
since the start of the Unix epoch:
midnight UTC of January 1, 1970 (not
counting leap seconds). Some systems
correctly handle negative time values,
w...
How to send a command to all panes in tmux?
I like to call :clear-history on panes with a huge scrollback. However, I want to script a way to send this command to all the panes in the various windows.
...
PHP CURL DELETE request
...
I finally solved this myself. If anyone else is having this problem, here is my solution:
I created a new method:
public function curl_del($path)
{
$url = $this->__url.$path;
$ch = curl_init();
curl_setopt($ch, CU...
Locking a file in Python
...terminate in such a way that the lock is left in place and you have to manually delete the lock before the file becomes accessible again. However, that aside, this is still a good solution.
– leetNightshade
Nov 8 '12 at 21:27
...
Batch File; List files in directory, only filenames?
...s is probably a very simple question, but I'm having trouble with it. Basically, I am trying to write a Batch File and I need it to list all the files in a certain directory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names and e...
How to define a List bean in Spring?
... stages in my application. It's configured that the necessary class (here called Configurator ) is injected with the stages.
Now I need the List of Stages in another class, named LoginBean . The Configurator doesn't offer access to his List of Stages.
...
Django: ImproperlyConfigured: The SECRET_KEY setting must not be empty
... Refactor to avoid circular dependency. The exact solution is really fairly specific to your own code.
– Sam Svenbjorgchristiensensen
Feb 17 '14 at 22:10
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