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C++

09/08/19

What is the effect of extern "C" in C++?

What exactly does putting `extern "C"` into C++ code do? For example: extern "C" { void foo(); }

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C++

09/07/19

How to Detect if I'm Compiling Code with a particular Visual Studio version?

Is there any way to know if I'm compiling under a specific Microsoft Visual Studio version?

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C++

09/07/19

How to use Boost in Visual Studio 2010?

What is a good step by step explanation on how to use the Boost library in an empty project in Visual Studio?

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C++

09/07/19

What is a "cache-friendly" code?

What is the difference between "**cache unfriendly code**" and the "**cache friendly**" code? How can I make sure I write cache-efficient code?

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C++

09/06/19

Unnamed/anonymous namespaces vs. static functions?

A feature of C++ is the ability to create unnamed (anonymous) namespaces, like so: namespace { int cannotAccessOutsideThisFile() { ... } } // namespace You would think that such a feature... more

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C++

09/06/19

How do I declare a 2d array in C++ using new?

How do i declare a 2d array using new? Like, for a "normal" array I would: int* ary = new int[Size] but int** ary = new int[sizeY][sizeX] a) doesn't work/compile and b) doesn't accomplish... more

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C++

09/06/19

In what cases do I use malloc vs new?

I see in C++ there are multiple ways to allocate and free data and I understand that when you call `malloc` you should call `free` and when you use the `new` operator you should pair with `delete`... more

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C++

09/06/19

When to use reinterpret_cast?

I am little confused with the applicability of `reinterpret_cast` vs `static_cast`. From what I have read the general rules are to use static cast when the types can be interpreted at compile time... more

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C++

09/06/19

Is inline assembly language slower than native C++ code?

I tried to compare the performance of inline assembly language and C++ code, so I wrote a function that add two arrays of size 2000 for 100000 times. Here's the code: #define TIMES 100000 ... more

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C++

09/03/19

Is uninitialized local variable the fastest random number generator?

I know the uninitialized local variable is undefined behaviour(*UB*), and also the value may have trap representations which may affect further operation, but sometimes I want to use the random... more

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C++

09/01/19

How do you clear a stringstream variable?

I've tried several things already, std::stringstream m; m.empty(); m.clear(); both of which don't work.

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C++

09/01/19

Can I call a base class's virtual function if I'm overriding it?

Say I have classes `Foo` and `Bar` set up like this: class Foo { public: int x; virtual void printStuff() { std::cout << x << std::endl; } }; ... more

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C++

09/01/19

When should you use a class vs a struct in C++?

In what scenarios is it better to use a `struct` vs a `class` in C++?

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C++

08/31/19

Iteration over std::vector: unsigned vs signed index variable?

What is the correct way of iterating over a vector in C++? Consider these two code fragments, this one works fine: for (unsigned i=0; i < polygon.size(); i++) { sum += polygon[i]; ... more

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C++

08/31/19

Forward declaring an enum in C++?

I'm trying to do something like the following: enum E; void Foo(E e); enum E {A, B, C}; which the compiler rejects. I've had a quick look on Google and the consensus seems to be "you... more

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C++

08/31/19

What are the rules about using an underscore in a C++ identifier?

It's common in C++ to name member variables with some kind of prefix to denote the fact that they're member variables, rather than local variables or parameters. If you've come from an MFC... more

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C++

08/30/19

What XML parser should I use in C++?

I have XML documents that I need to parse and/or I need to build XML documents and write them to text (either files or memory). Since the C++ standard library does not have a library for this, what... more

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C++

08/30/19

How do I get the directory that a program is running from?

Is there a platform-agnostic and filesystem-agnostic method to obtain the full path of the directory from where a program is running using C/C++? Not to be confused with the current working... more

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C++

08/30/19

Why does NaN - NaN == 0.0 with the Intel C++ Compiler?

It is well-known that NaNs propagate in arithmetic, but I couldn't find any demonstrations, so I wrote a small test: #include <limits> #include <cstdio> int main(int argc, char*... more

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C++

08/30/19

What is the easiest way to initialize a std::vector with hardcoded elements?

I can create an array and initialize it like this: int a[] = {10, 20, 30}; How do I create a `std::vector` and initialize it similarly elegant? The best way I know is: ... more

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C++

08/29/19

Concatenating two std::vectors?

How do I concatenate two `std::vector`s?

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C++

08/27/19

What is the easiest way to make a C++ program crash?

I'm trying to make a Python program that interfaces with a different crashy process (that's out of my hands). Unfortunately the program I'm interfacing with doesn't even crash reliably! So I want... more

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C++

08/25/19

Why does C++ not have reflection?

This is a somewhat bizarre question. My objectives are to understand the language design decision and to identify the possibilities of reflection in C++. 1. Why C++ language committee did not go... more

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C++

08/23/19

How to replace all occurrences of a character in string?

What is the effective way to replace all occurrences of a character with another character in `std::string`?

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C++

08/23/19

What's the best way to trim std::string?

I'm currently using the following code to right-trim all the `std::strings` in my programs: std::string s; s.erase(s.find_last_not_of(" \ \\r\ ")+1); It works fine, but I wonder if there are... more

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What is the effect of extern "C" in C++?

How to Detect if I'm Compiling Code with a particular Visual Studio version?

How to use Boost in Visual Studio 2010?

What is a "cache-friendly" code?

Unnamed/anonymous namespaces vs. static functions?

How do I declare a 2d array in C++ using new?

In what cases do I use malloc vs new?

When to use reinterpret_cast?

Is inline assembly language slower than native C++ code?

Is uninitialized local variable the fastest random number generator?

How do you clear a stringstream variable?

Can I call a base class's virtual function if I'm overriding it?

When should you use a class vs a struct in C++?

Iteration over std::vector: unsigned vs signed index variable?

Forward declaring an enum in C++?

What are the rules about using an underscore in a C++ identifier?

What XML parser should I use in C++?

How do I get the directory that a program is running from?

Why does NaN - NaN == 0.0 with the Intel C++ Compiler?

What is the easiest way to initialize a std::vector with hardcoded elements?

Concatenating two std::vectors?

What is the easiest way to make a C++ program crash?

Why does C++ not have reflection?

How to replace all occurrences of a character in string?

What's the best way to trim std::string?

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