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What is the 'override' keyword in C++ used for? [duplicate]
...m working on. May I know, what is real use of override , perhaps with an example would be easy to understand.
4 Answers
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How to call a parent class function from derived class function?
How do I call the parent function from a derived class using C++? For example, I have a class called parent , and a class called child which is derived from parent. Within
each class there is a print function. In the definition of the child's print function I would like to make a call to the ...
What is “vectorization”?
...d this term in matlab, fortran ... some other ... but I've never found an explanation what does it mean, and what it does? So I'm asking here, what is vectorization, and what does it mean for example, that "a loop is vectorized" ?
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Is Hash Rocket deprecated?
...well-cited RIP Hash rocket post would seem to imply the Hash Rocket syntax ( :foo => "bar" ) is deprecated in favor of the new-to-Ruby JSON-style hash ( foo: "bar" ), but I can't find any definitive reference stating the Hash Rocket form is actually deprecated/unadvised as of Ruby 1.9.
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Why does “pip install” inside Python raise a SyntaxError?
...kage. I try to run pip install from the Python shell, but I get a SyntaxError . Why do I get this error? How do I use pip to install the package?
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What happens to a declared, uninitialized variable in C? Does it have a value?
...ic variables (file scope and function static) are initialized to zero:
int x; // zero
int y = 0; // also zero
void foo() {
static int x; // also zero
}
Non-static variables (local variables) are indeterminate. Reading them prior to assigning a value results in undefined behavior.
void foo() {
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What to do Regular expression pattern doesn't match anywhere in string?
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Contrary to all the answers here, for what you're trying to do regex is a perfectly valid solution. This is because you are NOT trying to match balanced tags-- THAT would be impossible with regex! But you are only matching what's in one tag, and that's perfectly regular.
Here's the problem,...
What happens if I define a 0-size array in C/C++?
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An array cannot have zero size.
ISO 9899:2011 6.7.6.2:
If the expression is a constant expression, it shall have a value greater than zero.
The above text is true both for a plain array (paragraph 1). For a VLA (variable length array), the behavior is undefined if the expression's valu...
Why is unsigned integer overflow defined behavior but signed integer overflow isn't?
...ed integer overflow is well defined by both the C and C++ standards. For example, the C99 standard ( §6.2.5/9 ) states
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Regex group capture in R with multiple capture-groups
In R, is it possible to extract group capture from a regular expression match? As far as I can tell, none of grep , grepl , regexpr , gregexpr , sub , or gsub return the group captures.
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