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Stack, Static, and Heap in C++
...t understood very well these three concepts. When do I have to use dynamic allocation (in the heap) and what's its real advantage? What are the problems of static and stack? Could I write an entire application without allocating variables in the heap?
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Difference between malloc and calloc?
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calloc() gives you a zero-initialized buffer, while malloc() leaves the memory uninitialized.
For large allocations, most calloc implementations under mainstream OSes will get known-zeroed pages from the OS (e.g. via POSIX mm...
How to create fixed space and flexible space bar button items programmatically?
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UIBarButtonItem *fixedItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
fixedItem.width = 20.0f; // or whatever you want
UIBarButtonItem *flexibleItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem...
What is a Memory Heap?
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Presumably you mean heap from a memory allocation point of view, not from a data structure point of view (the term has multiple meanings).
A very simple explanation is that the heap is the portion of memory where dynamically allocated memory resides (i.e. memory ...
How is Python's List Implemented?
...em[0], etc. */
PyObject **ob_item;
/* ob_item contains space for 'allocated' elements. The number
* currently in use is ob_size.
* Invariants:
* 0 <= ob_size <= allocated
* len(list) == ob_size
* ob_item == NULL implies ob_size == allocated == 0
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Does using “new” on a struct allocate it on the heap or stack?
...hen you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ?
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Why would I make() or new()?
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Go has multiple ways of memory allocation and value initialization:
&T{...}, &someLocalVar, new, make
Allocation can also happen when creating composite literals.
new can be used to allocate values such as integers, &int is illegal:
new(P...
Difference in make_shared and normal shared_ptr in C++
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The difference is that std::make_shared performs one heap-allocation, whereas calling the std::shared_ptr constructor performs two.
Where do the heap-allocations happen?
std::shared_ptr manages two entities:
the control block (stores meta data such as ref-counts, type-erased del...
How to remove/delete a large file from commit history in Git repository?
...ou run above code, you will get nice human-readable output like this:
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0d99bb931299 530KiB path/to/some-image.jpg
2ba44098e28f 12MiB path/to/hires-image.png
bd1741ddce0d 63MiB path/to/some-video-1080p.mp4
???? Fast File Removal ????
Suppose you then want to remove the files a and b from ...
Why should I use a pointer rather than the object itself?
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It's very unfortunate that you see dynamic allocation so often. That just shows how many bad C++ programmers there are.
In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should w...