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Fastest way to reset every value of std::vector to 0
...ATIONS = 100000;
const size_t TEST_ARRAY_SIZE = 10000;
int main(int argc, char** argv) {
std::vector<int> v(TEST_ARRAY_SIZE, 0);
for(size_t i = 0; i < TEST_ITERATIONS; ++i) {
#if TEST_METHOD == 1
memset(&v[0], 0, v.size() * sizeof v[0]);
#elif TEST_METHOD == 2
...
What and where are the stack and heap?
...ate a lot of data.
Responsible for memory leaks.
Example:
int foo()
{
char *pBuffer; //<--nothing allocated yet (excluding the pointer itself, which is allocated here on the stack).
bool b = true; // Allocated on the stack.
if(b)
{
//Create 500 bytes on the stack
char buffer[50...
How to un-escape a backslash-escaped string?
...WARNING: value.encode('utf-8').decode('unicode_escape') corrupts non-ASCII characters in the string. Unless the input is guaranteed to only contain ASCII characters, this is not a valid solution.
– Alex Peters
Jun 9 '19 at 11:46
...
Is there an equivalent for var_dump (PHP) in Javascript?
...ts, add three to it and
// use it to indent the out block by that many characters. This argument is
// not intended to be used by any other than the recursive call.
var indent_by = typeof arguments[3] === 'undefined' ? 0:arguments[3]+3;
var do_boolean = function (v)
{
r...
MIN and MAX in C
... 3rd operand against each other. For example, the result of GENERIC_MAX(my_char1, my_char2) would be an int. To prevent the macro from doing such potentially dangerous type promotions, a final type cast to the intended type was used.
Rationale
We want both parameters to the macro to be of the same...
What is the minimum I have to do to create an RPM file?
...ion: 1.0
Release: 1
Summary: Short description (first char has to be uppercase)
License: GPL
URL: www. your_website/
BuildRequires: package_required >= (or ==, or <=) 1.0.3 (for example)
%description
Description with almost 79 characters (first char h...
When should I use perror(“…”) and fprintf(stderr, “…”)?
...
perror(const char *s): prints the string you give it followed by a string that describes the current value of errno.
stderr: it's an output stream used to pipe your own error messages to (defaults to the terminal).
Relevant:
char *stre...
What's best SQL datatype for storing JSON string?
...d as of SQL Server 2005 and should not be used for new development. Use VARCHAR(MAX) or NVARCHAR(MAX) instead
IMAGE, VARBINARY(MAX) : IMAGE is deprecated just like TEXT/NTEXT, and there's really no point in storing a text string into a binary column....
So that basically leaves VARCHAR(x) or NVARC...
Left-pad printf with spaces
...
If you want the word "Hello" to print in a column that's 40 characters wide, with spaces padding the left, use the following.
char *ptr = "Hello";
printf("%40s\n", ptr);
That will give you 35 spaces, then the word "Hello". This is how you format stuff when you know how wide you wa...
Should I use static_cast or reinterpret_cast when casting a void* to whatever
...g between pointer types (as is fairly common when indexing in memory via a char*, for example), static_cast will generate a compiler error and you'll be forced to use reinterpret_cast anyway.
In practice I use reinterpret_cast because it's more descriptive of the intent of the cast operation. You c...