C++ - Страница 1258

Let's say you have a table

Customer | Product Dave | Sneakers Martin | Tooth Brush Andrew | Shirt Dave | Tooth Brush In SQL, you can do

SELECT Customer, Product, DENSE_RANK() OVER (ORDER BY Customer) AS customer_id, DENSE_RANK() OVER (ORDER BY...

I wrote the following code that has two lambdas. One of them explicitly captures i while the other doesn't. Note i is constexpr so we don't need to capture it explicitly.

My question is why func(lambda2) doesn't compile while func(lambda) does?...

Please help me!

This is a part of my code, I try to use opencv and mfc in Visual Studio 2022.

void CLicensePlateRecognitionDlg::OnBnClickedBtnLoadImage() { CString file_name = _T( D:/Image Processing/Test/1.jpg ); Mat src = imread( D:/Image...

If we have a type T that is not copy-constructible but copy-assignable:

struct T { T() = default; ~T() = default; T(const T&) = delete; T(T&&) = default; T& operator=(const T&) = default; T& operator=(T&&) = default; }; then...

I have used the glfwgetwindowpos and glfwsetwindowpos with imgui's getmousedragdelta to try and move the parent glfw window using imgui. What I am trying to accomplish is to have an imgui window where I am able to drag on it, but rather than moving...

I'm having some troubles cross compiling Qt6 on Ubuntu 22.04 using mingw64 and CMake. The compilation process starts fine and all source files get compiled, but when I start looking for Qt components using

find_package(Qt6 REQUIRED COMPONENTS Core...

My team has encountered a deadlock that I suspect is a bug in the Windows implementation of SRW locks. The code below is a distilled version of real code. Here's the summary:
Main thread acquires exclusive lock Main thread creates N children...

Please help me!

This is a part of my code, I try to use opencv and mfc in Visual Studio 2022.

CString file_name = _T( D:/Image Processing/Test/1.jpg ); Mat src = imread( D:/Image Processing/Test/1.jpg ); CImage image; image.Load(file_name); Why...

You are the coach of a basketball team with a maximum total player capacity of K. You have a list of player types of size N, where each player of one type contributes a certain number of points to the team's overall points, and the number of players...

I have used the glfwgetwindowpos and glfwsetwindowpos with imgui's getmousedragdelta to try and move the parent glfw window using imgui. What I am trying to accomplish is to have an imgui window where I am able to drag on it, but rather than moving...

enter image description hereI had downloaded the mingw compiler for compiling C program source code and also have pasted its bin folder location in the environment variable PATH . The command prompt also tells me that the compiler is installed in...

Platform: Windows 10, Visual Studio VC142

I'm using Boost 1.80.0 in my project. I've built Boost and been using modules such as Container without issue , however I tried to use Boost.Serialization and I get a link error:

LINK : fatal error...

I have a class StreamRead that represents a file, that I'd like to pass to a constructor for other classes, like a Bitmap for instance. However, I cannot pass an unnamed temporary to Bitmap directly.

Bitmap::Bitmap(StreamRead & in) { // in cannot...

I'm currently trying to create a game in C++17 with SDL2 (and SDL_ttf). When I'm trying to initialize the text renderer, I'm getting an error that says: Exception thrown at 0x00007FFFB5A19116 (SDL2_ttf.dll) in projVSC.exe: 0xC0000005: Access...

#include using namespace std; class Myclass{ public: int a=3; Myclass& operator=(const Myclass& obj){ a=obj.a; return *this; } Myclass operator+(Myclass& obj){ Myclass temp; temp.a=a+obj.a; return temp; } }; int main() { Myclass A; Myclass B; B=A+B;...

I wrote the following code that has two lambdas. One of them explicitly captures i while the other doesn't. Note i is constexpr so we don't need to capture it explicitly.

My question is why func(lambda2) doesn't compile while func(lambda) does?...

I am serializing a set of contents, indexed by multiple properties using boost::multi_index_container, and a params struct, into a binary archive which I want to deserialize latter. But the archive created using boost 1.74 is unreadable (Invalid or...

I am currently working on a project involving property handlers, specifically targeting .txt files. As a newcomer to this field, I have encountered an issue that I'm struggling to resolve and would greatly appreciate your guidance.

My objective is...

If we have a type T that is not copy-constructible but copy-assignable:

struct T { T() = default; ~T() = default; T(const T&) = delete; T(T&&) = default; T& operator=(const T&) = default; T& operator=(T&&) = default; }; then...

I have a small project which I've refactored into C++ modules. Below is CMakeLists.txt :

cmake_minimum_required(VERSION 3.28) project(myengine LANGUAGES CXX) set(CMAKE_CXX_STANDARD 20) set(CMAKE_CXX_STANDARD_REQUIRED ON)...

I am trying to make a simple tool that requires some lookup on a fixed key-value dataset, so I try to lazily throw all data to a hashmap in the header file:

/** main.h */ #include #include using namespace std; const unordered_map test = {...

I am trying to make an application where there is a looping background music. I have added the bgm m4a file into the project via CMake. The code in MainWindow is below.

ui->setupUi(this); screamer = new QMediaPlayer(this); audioOutput = new...

I am making a REST request to Gmail API.

I am authorized for the scope:

According to the documentation:

Making a PUT request to will update the settings.

So I read the settings first (GET

As a result I get this JSON:

{ enabled : true,...

Windows 11, Visual Studio 2022, C++, MFC I created an app and edited in a few controls. One is named c_quadratic_input. When searching the code the name is not found. Where can I find a tutorial that tells me how to use this item?

It gets worse....

Visual studio shows 0 issues found but when program starts, a tab pop up with vector library and points on line 2151 and says

Unhandled exception at 0x00007FF90121CF19 in Project2.exe: Microsoft C++ exception: std::out_of_range at memory location...