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Why was “Avoid Enums Where You Only Need Ints” removed from Android's performance tips?
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TLDR: Dalvik was not good with memory allocation and Enum uses more memory than int. Android Lollipop replaced Dalvik with ART which does not suffer from the same limitations. Thus this recommendation is not relevant anymore.
The long answer:
Wow! 8 years, 5 a...
Determine the number of lines within a text file
...ne loads the entire contents of the file into an array which means it must allocate at least as much memory as the size of the file. The second merely loops one line at a time so it never has to allocate more than one line's worth of memory at a time. This isn't that important for small files, but f...
What do the plus and minus signs mean in Objective-C next to a method?
...se?
[CustomClass classMethod];
CustomClass *classObject = [[CustomClass alloc] init];
[classObject instanceMethod];
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How do I concatenate two strings in C?
....h>
char* concat(const char *s1, const char *s2)
{
char *result = malloc(strlen(s1) + strlen(s2) + 1); // +1 for the null-terminator
// in real code you would check for errors in malloc here
strcpy(result, s1);
strcat(result, s2);
return result;
}
This is not the fastest wa...
Array versus linked-list
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@Rick, vectors typically overallocate the space they require so that they don't need to allocate new space everytime the size increases. The result is that vectors are typically much less memory intensive, not more then linked lists.
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Quickly create large file on a Windows system
...oftware/rdfc/index-en.html
RDFC is probably not the fastest, but it does allocate data blocks. The absolutely fastest would have to use lower level API to just obtain cluster chains and put them into MFT without writing data.
Beware that there's no silver bullet here - if "creation" returns insta...
Programmatically add custom event in the iPhone Calendar
... {
[super viewDidLoad];
EKEventStore *eventStore = [[EKEventStore alloc] init];
EKEvent *event = [EKEvent eventWithEventStore:eventStore];
event.title = @"EVENT TITLE";
event.startDate = [[NSDate alloc] init];
event.endDate = [[NSDate alloc] initWithTimeInterval:600...
Best practices for Storyboard login screen, handling clearing of data upon logout
...oller"];
UINavigationController* navigation = [[UINavigationController alloc] initWithRootViewController:rootController];
self.window.rootViewController = navigation;
}
In SignUpViewController.m file
- (IBAction)actionSignup:(id)sender
{
AppDelegate *appDelegateTemp = [[UIApplication...
Differences between std::make_unique and std::unique_ptr with new
...untime efficiency the way using make_shared does (due to avoiding a second allocation, at the cost of potentially higher peak memory usage).
* It is expected that C++17 will include a rule change that means that this is no longer unsafe. See C++ committee papers P0400R0 and P0145R3.
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Append value to empty vector in R?
... avoided".
As BrodieG mentioned in the comments: it is much better to pre-allocate a vector of the desired length, then set the element values in the loop.
Here are several ways to append values to a vector. All of them are discouraged.
Appending to a vector in a loop
# one way
for (i in 1:le...