C++ - Страница 1242

Я создавал дисплей, управляемый через Bluetooth, используя Qt и raspberrypi. На raspberrypi будет работать служба Bluetooth, и когда я подключусь к BluetoothServer. Пользователь может выбрать либо отображение сообщения, либо загрузку и отображение...

У меня проблема с потоками ввода-вывода в C++. Мне нужно написать программу, которая считывает данные из файла и записывает их в другой файл. Команда в CMD должна выглядеть так: «программа файл2». Имена файлов должны быть предоставлены пользователем...

Можно ли в C++ выполнять перечисление (либо во время выполнения, либо во время компиляции (предпочтительно)) и вызывать функции/генерировать код для каждой итерации?

Пример вариант использования:

enum abc
{
start
a,
b,
c,
end
}
for each...

В «Букваре C++» Стэнли Липпмана на странице 234 упоминается, что

Обычно объявлять функцию локально — плохая идея. Однако
чтобы объяснить, как область видимости взаимодействует с перегрузкой, мы нарушим эту
практику и будем использовать объявления...

Рассмотрим пример ниже. Предположим, что barrier is initialized to 0.
There is one producer thread and two consumer threads that constantly check barrier . If the barrier is set, they decrease runcnt . The producer thread waits for runcnt to reach...

Я знаю это std::shared_ptr et al emulate covariance by having templated constructors.
But let's say I have an abstract base class that's a simple accessor:
template
class Reader {
public:
virtual const T& Get() const = 0;
};

Then if I have a...

If I have an enum that does not assign numbers to the enumerations, will its ordinal value be 0? For example:
enum enumeration { ZERO,
ONE,
TWO,
THREE,
FOUR,
FIVE,
SIX,
SEVEN,
EIGHT,
NINE };

I've been able to find a post citing that the C99...

I've been experimenting with the enum class feature of C++ and successfully got the ++ operator to overload as follows:
enum class counter_t : uint8_t {VAL1 = 0, VAL2, VAL3, VAL4, END};

inline counter_t operator ++ (counter_t c, int) {
counter_t...

I have two classes: a Parent class and a Child class (inheriting from the Parent class). I would like to know if it is possible to cast/transform a Child** to a Parent** with reinterpret_cast or something else. Is such a thing possible?
Below is a...

I have a problem with I/O streams in c++. I have to write a program which read data from file and writes it into another file. Command in CMD should be like: program file2 . The names of the files should be provided by the user (could be...

See following code:
#include
#include
#include
#include

class exception_t
: public std::exception
{
public:
template
exception_t(std::string_view users_fmt, args_t&&... args)
: m_users_fmt(users_fmt)
,...

#include

using namespace std;
class T1
{
const int t = 100;
public:

T1()
{
cout

Источник:

I'm working on my PHD and need an (well known and tested) C/C++ library that gives an exact solution for the TSP problem to compare with my heuristics.

Источник:

I've been developping my first flutter app using flutlab and have recently set things up in vscode. Everything works fine in the web emulator but when I try to run for linux I get the following error:
Launching lib/main.dart on Linux in debug...

I'm new in the raspbian bios and programming language, I have problem with receiving data from the raspberry pi 4 uart (ttyS0). I have ADC converter of course, which returns me hexadecimal string with data. The Przemytnik class is for connecting c++...

I’d like to write some native code in C or C++ to be used with Swift on iOS. This code would mainly be invoked from Swift but would also need to callback to Swift as well, like shown in this diagram:

What is the mechanism for interfacing Swift...

I would like to have objects add a pointer pointing to themselves into a map which is a member of another class.
Here is what I have so far:
// entitymanager.h
// Inside the public part of the EntityManager class
std::map AllMapEntities;

//...

I was building a bluetooth controlled display using Qt and raspberrypi.The raspberrypi will have a bluetooth service running on it and when I connect to the BluetoothServer. The user can choose to either a display a message or upload and display an...

I am using C++ Winforms. So I have a Control in my form.
Now what I want to do is something like this to check if a control is a TextBox :
if (control is TextBox)
{
// ...
}

In C# you can do the above I believe. But how can I do the same in C++...

template
class Prop {
public:
Prop(const std::function &getter) : getter(getter) {}
Prop(const T &value) : getter( () { return value; }) {}
Prop(const char *value) : getter( () { return std::string(value); }) {}

T operator()() const {
return...

I am trying to port a C++ library with a C calling convention to C#.
The project is at
I am trying to port the sample C++ application and use the .DLL from the Lepcc C++ project.
I am getting an access violation (memory corrupt) when the...

I have a Qt application which uses pybind to embed python plugins providing some kind of handlers. From what I have read online gluing the event loops is nearly impossible. Now I wonder if it is possible to run an asyncio event loop in a c++...

I want to inherit from a template class with a type defined in the derived class. I dont want to use composition because if I do so, I have to give public access to the vector or write some methods for each object in order to interact with the...

please ignore my bad coding practice i cant for the life of me figure out how classes in C work nevermind in visual studio as before this i only coded in java in eclipse XD
but here is my messy code
#include
#include
#include
#include
#include...

I'm trying to optimize my 3D rendering OpenCL code. Currently, I render a 3D triangle by dividing its bounding box into 2x2 tiles and doing necessary computations for each pixel inside the tile. This turned out to be slightly faster than giving each...