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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...
How do I declare and initialize an array in Java?
...turning it to the caller, it is no longer valid. Using the new keyword you allocate the new object from the heap and it is valid outside the defining scope.
– teukkam
Oct 18 '16 at 9:55
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How to read integer value from the standard input in Java
...Scanner in = new Scanner(System.in);
int num = in.nextInt();
It can also tokenize input with regular expression, etc. The API has examples and there are many others in this site (e.g. How do I keep a scanner from throwing exceptions when the wrong type is entered?).
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Creating an object: with or without `new` [duplicate]
...e the object creation occurs at runtime. (I won't go into the specifics of allocating dynamic arrays here.)
Neither is preferred; it depends on what you're doing as to which is most appropriate.
Use the former unless you need to use the latter.
Your C++ book should cover this pretty well. If you...
Using arrays or std::vectors in C++, what's the performance gap?
...rator is the same damn thing as
// incrementing a pointer.
Note: If you allocate arrays with new and allocate non-class objects (like plain int) or classes without a user defined constructor and you don't want to have your elements initialized initially, using new-allocated arrays can have perfor...
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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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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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...
How do I clear the std::queue efficiently?
...uivalent. Since there is no transfer of ownership in the assignment of the allocated memory some containers (like vector) might just call the destructors of the previously held elements and set the size (or equivalent operation with the stored pointers) without actually releasing the memory.
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