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Why are hexadecimal numbers prefixed with 0x?
...his is great because
an integer constant now always consists of a single token,
the parser can still tell right away it's got a constant,
the parser can immediately tell the base (0 is the same in both bases),
it's mathematically sane (00005 == 05), and
no precious special characters are needed (a...
Constant Amortized Time
... takes constant time (that is, O(1)). But each time the array is full, you allocate twice as much space, copy your data into the new region, and free the old space. Assuming allocates and frees run in constant time, this enlargement process takes O(n) time where n is the current size of the array.
...
How do I iterate over an NSArray?
...ion, without having to worry about the bureaucracy of memory management, reallocation etc. Of course this does come at a cost though. I think it's pretty obvious that say using an NSArray of NSNumbers is going to be slower than a C Array of floats for simple iterations, so I decided to do some tests...
fatal: The current branch master has no upstream branch
...because you don't want to generate a secondary key, a PAT: personal Access Token), then you can switch to ssh, as I have shown here.
As noted by qwerty in the comments, you can automatically create the branch of same name on the remote with:
git push -u origin head
Why?
HEAD (see your .git\...
Batch equivalent of Bash backticks
...tionality using cmd.exe scripts with the for /f command:
for /f "usebackq tokens=*" %%a in (`echo Test`) do my_command %%a
Yeah, it's kinda non-obvious (to say the least), but it's what's there.
See for /? for the gory details.
Sidenote: I thought that to use "echo" inside the backticks in a "f...
How can I use pointers in Java?
...ystem will throw an exception (OutOfMemoryError) when you call new and the allocator cannot allocate the requested cell. This is very rare and usually results from run-away recursion.
Note that, from a language point of view, abandoning objects to the garbage collector are not errors at all. It is ...
Programmatically open Maps app in iOS 6
...ordinate2DMake(16.775, -3.009);
MKPlacemark *placemark = [[MKPlacemark alloc] initWithCoordinate:coordinate
addressDictionary:nil];
MKMapItem *mapItem = [[MKMapItem alloc] initWithPlacemark:placemark];
[mapItem setName:@"My Place"];
// Pas...
How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...ably so that the programmer can't create programs that have runaway memory allocation without running into this problem and having to examine exactly what they are doing).
So this given there are several approaches you could take to either determine what amount of memory you need or to reduce the a...
Can I access constants in settings.py from templates in Django?
...values out of the settings.
@register.tag
def value_from_settings(parser, token):
try:
# split_contents() knows not to split quoted strings.
tag_name, var = token.split_contents()
except ValueError:
raise template.TemplateSyntaxError, "%r tag requires a single argume...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
...----- -------- -------------------------
0xCD Clean Memory Allocated memory via malloc or new but never
written by the application.
0xDD Dead Memory Memory that has been released with delete or free.
It is used to detect w...