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.NET List Concat vs AddRange
...ed execution, using Concat would likely be faster because it avoids object allocation - Concat doesn't copy anything, it just creates links between the lists so when enumerating and you reach the end of one it transparently takes you to the start of the next!
– Greg Beech
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Why is an int in OCaml only 31 bits?
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See the the "representation of integers, tag bits, heap-allocated values" section of https://ocaml.org/learn/tutorials/performance_and_profiling.html for a good description.
The short answer is that it is for performance. When passing an argument to a function it is either passe...
.NET unique object identifier
...utomatically so the information is correct.
Object IDs are 64-bit numbers. Allocation starts from one, so zero is never a valid object ID. A formatter can choose a zero value to represent an object reference whose value is a null reference (Nothing in Visual Basic).
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Is there a destructor for Java?
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Nope, no destructors here. The reason is that all Java objects are heap allocated and garbage collected. Without explicit deallocation (i.e. C++'s delete operator) there is no sensible way to implement real destructors.
Java does support finalizers, but they are meant to be used only as a safegu...
How to read the content of a file to a string in C?
... 0, SEEK_END);
length = ftell (f);
fseek (f, 0, SEEK_SET);
buffer = malloc (length);
if (buffer)
{
fread (buffer, 1, length, f);
}
fclose (f);
}
if (buffer)
{
// start to process your data / extract strings here...
}
...
How do I base64 encode (decode) in C?
... *output_length = 4 * ((input_length + 2) / 3);
char *encoded_data = malloc(*output_length);
if (encoded_data == NULL) return NULL;
for (int i = 0, j = 0; i < input_length;) {
uint32_t octet_a = i < input_length ? (unsigned char)data[i++] : 0;
uint32_t octet_b = ...
C++ Lock-free Hazard Pointer（冒险指针） - C/C++ - 清泛网 - 专注C/C++及内核技术
...re(const std::atomic<T *> &target) {
auto pointer = HazardPointer<T>::Alloc();
do {
pointer->target_ = target.load(std::memory_order_acquire);
} while (pointer->target_.load(std::memory_order_acquire) !=
target.load(std::memory_order_acquire));
return Holde...
Base64 Decoding in iOS 7+
...g(@"%@", base64String); // Zm9v
Decoding
NSData *decodedData = [[NSData alloc] initWithBase64EncodedString:base64String options:0];
NSString *decodedString = [[NSString alloc] initWithData:decodedData encoding:NSUTF8StringEncoding];
NSLog(@"%@", decodedString); // foo
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Make a program run slowly
...ll not slow down the execution speed per se, but will make Linux scheduler allocate less (and possibly shorter) execution time frames, preempt more often, etc. See Process Scheduling (Chapter 10) of Understanding the Linux Kernel for more details on scheduling.
You may want to increase the timer int...
How can I iterate over an enum?
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Except now you've actually allocated memory when an enum, provided it is zero-indexed and strictly continous, can do that task without allocating memory.
– Cloud
Jan 17 '14 at 23:02
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