You forgot to include the new header which provides standard library implementations of the placement new (as an alternative, you could provide your own implementations). The following code compiles and runs fine on my Linux box. #include...

C++17

C++

Segmented Map, a Compromise Between Flat Map and std::map

18 Sep 2022 by Mikhail Semenov

This article proposes a mapping algorithm, called Segmented Map, which is almost as fast as Flat Map is random access and enumeration of elements and close to std::map in insertion of elements.

How to Create High Performance (and Publication Quality) 2D Graphs in C++ using Morphologica

14 Mar 2023 by sebjameswml

Walks you through the steps needed to draw high quality 2D graphs in your C++ programs using the header-only library morphologica

This code is not printing anything I have tried different compilers

8 Jan 2024 by Richard MacCutchan

I think the problem is here: if (sock % m == 0) { sock++; } sock--; // If you add 1 to sock and then subtract 1 it will go on for ever but I am not sure what those lines of code are supposed to do.

C++17

C++17: Benchmark of Singular Min/Max and Iterator Versions

16 Jan 2020 by Shao Voon Wong

Benchmark of Singular Min/Max and Iterator Versions

C++17

C++

C++ - Lightweight Parsing Command Line Arguments

19 Sep 2020 by Daniel Petrovic

In this tip, I want to represent a quick lightweight possibility (one of many) for parsing command line arguments on the fly using C++17.

qTimeLineEditor - A flexible graphical time line editor for your animations

19 Sep 2020 by sdancer75

A graphical time line editor to help you create and prototype animations. It is useful for adjusting variables and checking out how the effects change over time with keyframing and easing/twining functions.

C++/WinRT Runtime Component in Win32 Applications - Part 2

17 Jan 2022 by Giuseppe Pischedda

Part 2 - Templates and variadic templates

C++17

C++

Dev

Enforcing a Static Interface in C++

2 Feb 2023 by Bruno van Dooren

Ways to enforce an interface contract on static methods, similar to what you would expect from static virtual methods if they'd exist in C++

Placement new? Why can't I read?

8 Nov 2023 by honey the codewitch

new expression - cppreference.com[^] Useless. Placement new operator in C++ - GeeksforGeeks[^] Bunk. Placement syntax - Wikipedia[^] Written by somebody who doesn't care if it's understood by anyone. Apparently I can't read code. Apparently...

C++17

C++

Convert a Win32 Project to WinUI3 Automatically

20 Jan 2024 by Michael Chourdakis

A set of tools to create a new VCXPROJ file automatically

New to programming...(help? )

13 Jun 2019 by Patrice T

Quote: Where should I start if I want to learn in a hands-on capacity. Google and YouTube ! You need to search for tutorials about the language and the GUI framework you choose. Google/YouTube tutorial c++ GUI framework Replace "framework" with its name when you know it. [Update] Quote: But if...

C++17

Implementation of Resizable Multidimensional Arrays in C++17

13 Nov 2019 by Mikhail Semenov

This article discusses an implementation of multidimensional array class with resizable dimensions. Access to subarrays and their swapping are allowed. Benchmarks are provided, which compare the performance of this implementation with Boost and standard C arrays.

C++17

Dev

Fundamental Type Specialization in C++

3 Jan 2020 by goranorsander

A class template for specializing fundamental types

Shooting Fibonacci Rabbits

17 Oct 2020 by George Shagov

Two and three states Fibonacci Rabbit's Machines

C++17

Why I am not able to declare the class in this program.

15 Dec 2020 by Richard MacCutchan

You need to use the correct syntax to access a function: shivam.get(); shivam.set(); Also it is not generally the best idea to have class functions getting console input. It is better to do that at the main level and then use set to...

C++17

C++

Why I am not able to declare the class in this program.

15 Dec 2020 by CPallini

As suggested, you could try a more idiomatic approach: #include using namespace std; class employee { int id; int count; public: employee(int id, int count): id(id), count(count){} void set_count(int new_count) { ...

C++17

C++

Force C++ to interpret line as a template function invocation instead of operator <

10 Apr 2021 by honey the codewitch

I'm trying to invoke a template function from inside another template, and the C++ compiler is getting confused trying to parse my code. Basically what's happening is it can't tell that my function is a template function. It thinks it's a field,...

C++17

C++

Force C++ to interpret line as a template function invocation instead of operator <

10 Apr 2021 by Greg Utas

This is fancier than anything I've done with templates, so I could be off base here. But recently there was a question involving the use of typename to explicitly flag a type within a template, and yours looks related to that, only a little...

C++17

C++

GFX Part 2: Device Independent Bitmaps

17 Apr 2021 by honey the codewitch

GFX IoT graphics library part 2 - device independent bitmaps

GFX Part 3: Drawing Primitives

25 Apr 2021 by honey the codewitch

Explore the basic drawing functionality provided by the GFX IoT library

How do I correct my output of "available rooms"?

8 Jan 2022 by Stefan_Lang

You are calling the display method on your Hotel object and that displays the Floors within that Hotel, but you never correctly initialized the Floor objects stored inside your Hotel object. Instead you created and initialized a separate Floor...

C++/WinRT Runtime Component in Win32 Applications - Part 3

14 Jan 2022 by Giuseppe Pischedda

How to create a Win32 C++ Application that "consumes" a C++/WinRT Component Runtime

Cc code output not working acc to given code.

3 Feb 2022 by M Imran Ansari

You are assigning in If block instead of checking the equality. Correct If condition if(num==0) { cout

C++17

Unable to get user input in the day 1 problem of advent of code 2022

5 Dec 2022 by OriginalGriff

Quote: The below code is what I have tried but it's entirely wrong! Yes. It is. And you don't know why. Fortunately, you have a tool available to you which will help you find out what is going on: the debugger. How you use it depends on your...

Having a problem getting the peb corrently

7 May 2023 by merano99

As Richard already pointed out, there are quite a few Windows system calls in the rest of the code and it would certainly be possible to get the pointer without assembler, but if you really want to, you can do it with VisualStudio and assembler. ...

MASM

C++17

ASM

MFC app edit control updating itself

23 Aug 2023 by Rick York

It is not entirely clear what you are trying to do. You state you want to have an edit control update itself but then you list it as CServicesDlg::EdtCompanyName(). That is clearly a method of a dialog class and it is unclear what relationship...

C++17

MFC

edit-control

MFC app - write something in first edit control to see in second edit control

1 Sep 2023 by merano99

Presumably the question again concerns an edit control in a dialog. There were already answers for this. MFC app edit control updating itself[^]

C++17

MFC

edit-control

MFC app - find if specific username wrote correct password

6 Sep 2023 by OriginalGriff

We can't tell, we have no access to your code while it is running, so we have no idea what is in m_RadIsntExist or what it should contain. So, it's going to be up to you. Fortunately, you have a tool available to you which will help you find out...

MFC app and run command "rundll32.exe dsquery.dll, openquerywindow"

30 Aug 2023 by Richard MacCutchan

Using AI is largely a waste of time to solve programming issues, or research "how to" questions. Microsoft provides a comprehensive set of documentation that you should make use of. Using ShellExecute runs the search in a separate Window. So...

This code is not printing anything I have tried different compilers

8 Jan 2024 by OriginalGriff

As soon as sock is divisible by m, it is incremented and immediately decremented again - so the next loop iteration has the same value of sock and the loop never exits. Since the loop never exits, the code never reaches the cout and you never see...

C++17

Is this a compiler bug or my bug?

20 Mar 2018 by Jochen Arndt

The destructor is called when the object goes out of scope. That is after the add() call in your code. But the rounding mode affects also string conversions. So the difference in the output is not created by the add() operations but by printing out the results: - With resetting the mode cout...

C++17

Problem compiling shared_ptr with arrays c++17 mac OS

30 Nov 2018 by CPallini

Yes, it looks a compiler problem (at least g++-7 compiles it without complaining). Why don't you an std::array, instead auto myArray = std::make_shared>(); ?

C++17

macOS

Error LNK2019: unresolved external symbol on phidgets code

30 Mar 2020 by Maciej Los

Please, follow the instruction from MSDN: Linker Tools Error LNK2019 | Microsoft Docs[^]

C++17

VS2019

Error LNK2019: unresolved external symbol on phidgets code

31 Mar 2020 by steveb

Did you include the .LIB file in your linker input?

C++17

VS2019

Why I am not able to declare the class in this program.

15 Dec 2020 by Member 12982558

get and set are functions and need parentheses

C++17

C++

GFX Part 1: A Device Agnostic Pixel

11 Apr 2021 by honey the codewitch

A device independent graphics library for IoT devices. Part 1 of a series.

The answer to the equation

28 Apr 2021 by Rick York

This is not a code conversion service but I will give you a hint. The Pascal for loop of this form : for x1 :=0 to 12 do looks like this in c++ : for( x1 = 0; x1

Best way to debug a C++ DLL in release mode

3 Aug 2021 by Stefan_Lang

We're developing plugins for a third party executable with a C++ API. There is no SDK available for the executable, and, worse, no debug version. The API uses at the very least std::vector and MFC CString which to my knowledge are not compatible...

C++17

VS2019

Best way to debug a C++ DLL in release mode

1 Aug 2021 by KarstenK

In this cases I like to write a log file with the debug texts and some error messages. Best is to check the amount of written data in some debug tests and only log errors and problems. Normally the problematic code areas are knows so concentrate...

C++17

VS2019

Best way to debug a C++ DLL in release mode

2 Aug 2021 by Greg Utas

Release builds have reached the point where the trade-off between performance and debugging is unacceptable. I'm using VS2017 and face the same problems. Here[^] are the compiler settings I use. They help, but it's still not as easy as a debug...

C++17

VS2019

Best way to debug a C++ DLL in release mode

2 Aug 2021 by Rick York

When I have done this I disabled optimizations in the release build of the library and enabled writing of the debug symbols file. I then set the hosting executable program for debugging the library to be the one in question and then set break...

C++17

VS2019

I am unable to change the bitmap images dispayed on an outlookbar style propertysheet

20 Oct 2021 by KarstenK

The MS controls are creating an own copy of the bitmaps. So when you want to change them, you need to destroy the control and recreate a new object with the new bitmaps.

C++17

MFC

Win32

Expression must have a constant value. However, putting constant value doesn't change anything

25 Oct 2021 by k5054

You don't say what compiler/OS you are using, but since this above snippet is accepted by gcc, I am guessing that you are using MSVC, which does not support variable length arrays. You will have to use dynamic memory allocation to create an...

C++17

C++

Cc code output not working acc to given code.

3 Feb 2022 by Tony Hill

You are not testing num for 0 correctly. You should do if(num == 0) not if (num=0) In your code you are assigning 0 to num because you are using a single equals sign which will be successful which the if statement evaluates to...

C++17

How to convert system command output to string ?

16 Oct 2022 by merano99

The command system() creates a new process to handle the specified command. char cmd[10]; strcpy(cmd, "dir"); system(cmd); In most cases, this is neither performant nor useful. But of course you can start a process with C this way. You could...

How to convert system command output to string ?

19 Oct 2022 by Alexandrnn

#include #include int main() { system("dir"); puts((char*)stdin); } #include #include #include int main() { char cmd[10]; strcpy_s(cmd, 10, "dir"); system(cmd); puts((char*)stdin); }

How to delete a key from the registry using C++ ?

20 Oct 2022 by Rick York

Have you investigated the RegDeleteKeyExA function (winreg.h) - Win32 apps | Microsoft Learn[^] ? Here is another sample : Deleting Registry Key with Subkeys Win32 C program example[^]

Unable to get user input in the day 1 problem of advent of code 2022

5 Dec 2022 by merano99

Saving the calories in a vector would be a good idea. std::vector numbers; Then it would be practical to write the calories as described in a file calories.txt and read this file line by line. At each blank line write the sum into the...

How can I code this poject

26 Mar 2023 by Rick York

Here is one place to start : cplusplus.com : fgets[^]. The sample code shows you how to open a file, read from it, and close it. That's what you need to do to read the data from the file. This function - cplusplus.com : atoi/[^], can be used...

C++17

Indexing into a bitmap problem

20 Aug 2023 by honey the codewitch

I have an issue where I'm writing out a simple 8-bit grayscale bitmap as I read it from a stream. The issue is this: I'm going top to bottom left to right, and attempting to read the pixels out of the bitmap sequentially. I feel like this...

C++17

C++

Indexing into a bitmap problem

20 Aug 2023 by Andre Oosthuizen

From what I could read (might be missing the ball completely) - There shouldn't be a need for the extra seek operation, as you're already calculating the offset based on the pixel's position. It is possible that the issue might be related to the...

C++17

C++

MFC app edit control updating itself

26 Aug 2023 by merano99

Rick has already written the basic solution in Solution1, here again in more detail: To display a summary of three other text fields in the text field EdtDescription, a simple solution would be to react on EN_CHANGE of the three fields and call...

C++17

MFC

edit-control

MFC app - write something in first edit control to see in second edit control

1 Sep 2023 by OriginalGriff

That's a little complicated, because generally speaking two instances of a control shouldn't even know that the other exists - it breaks OOPs principles if they do, unless one is the child of another (and parent-child is trivial, so I'm pretty...

C++17

MFC

edit-control

MFC app - write something in first edit control to see in second edit control

1 Sep 2023 by Richard MacCutchan

You cannot expect there to be YouTube tutorials on every question you come up with. As already suggested, you should use the documentation to check what features are available in each control that you are using: CEdit Class | Microsoft Learn[^].

C++17

MFC

edit-control

MFC app - combobox that adds users or groups from any folder

29 Aug 2023 by Richard MacCutchan

Your time would be better spent studying the documentation for the CComboBox Class | Microsoft Learn[^]. It is a simple matter to use one of the Findxxx methods to checlk if an entry already exists before adding it to the list.

C++17

MFC

combobox

MFC app and run command "rundll32.exe dsquery.dll, openquerywindow"

30 Aug 2023 by Dave Kreskowiak

Why would you want to launch an entirely separate process (rundll32) that will not communicate with your app at all? Using the query window will do nothing in your application. You app will never know the user did anything in that window because...

From Modern to Unbelievably Modern C++

20 Jun 2023 by Coral Kashri

CoreC++ talk - experience summarize, and self opinions

C++17

C++

Eliminate this right shift count warning

4 Oct 2023 by OriginalGriff

Have you tried ANDing it with 111111b? Since the value can't be bigger than 63 that might shut the compiler up?

C++17

How do I create a C++ console program that does not show a screen?

24 Jan 2024 by Dave Kreskowiak

A better choice would be a Windows Service since they have no UI at all. Trying to do this as a normal, user launchable app seems ... suspicious.

C++17

Windows

How do I create a C++ console program that does not show a screen?

24 Jan 2024 by Maxim Kartavenkov

You can create regular windows application not the console application, just do not create any dialogs and proceed like you do as you had the console application. There will be just linker configuration change and the function WinMain instead of...

C++17

Windows

How do I create a C++ console program that does not show a screen?

24 Jan 2024 by k5054

It's not clear what you're trying to achieve. If you want to create a service, then you should follow the advice in Solution 1. If you're trying to create a commandline utility, like copy for example, then what you're doing is probably what you...

C++17

Windows

Why this udp socket not work when I run it in pc outside the network ?

26 Sep 2022 by Death Smoke

I'm trying to make a connection between two computers both of them are using tp-link adapter , but i'm not receving anything from client . #include #include using namespace std; int main() { ...

Is this a compiler bug or my bug?

20 Mar 2018 by Member 3733166

Run the the following program twice. Once with the given destructor and once with "std::fesetround(value);" removed from the destructor. Why do I receive different outputs? Shouldn't destructor be called after function "add"? #include #include #include struct...

C++17

Is this a compiler bug or my bug?

20 Mar 2018 by CPallini

It is a cout artifact. Try, for instance std::cout

C++17

Problem compiling shared_ptr with arrays c++17 mac OS

30 Nov 2018 by Member 14068785

Dear experts, I have a simple code which uses shared_ptr with arrays. The line of the code that gives problem is: std::shared_ptr myArray(new double[10]); I'm using a Mac OS 10.14.1 and Xcode 10.1 from command line: c++ -std=c++17 -o sharedPtr sharedPtr.cpp Apparently I think it...

C++17

macOS

How to consume c++17 modules in managed code?

11 Mar 2019 by Member 10068530

I want to consume c++17 modules from managed clr/c++ code. Is it possible? What I have tried: I have built a dll with c++ modules. Consumed it from a console application without turning /clr. Everything worked. Once i turn on /clr switch, it does not work. My clr console application has...

C++17

modules

CLR

How to consume c++17 modules in managed code?

11 Mar 2019 by steveb

There are many ways you can do that: 1. Implement your C++ 17 as DLL and export "C" function interface. There are ton of material on google how to call DLLs from CLR or .Net langs. 2. Implement as COM DLL. This one can be called by any language VB, C#, C++, C etc 3. Implement as COM EXE server....

C++17

modules

CLR

How do I create a button in C++

26 May 2019 by Member 14470453

I have created a project in Dev C++, but I need to create a window and control mouse events over a button. Could you help me please? What I have tried: I used next cod, but it do not works properly // Grafica de la circunferencia //#include #include #include ...

C++17

How do I create a button in C++

26 May 2019 by Tonex247

Buttons are actually windows and are created same way: #define btn_ID 5000 //used as the button's id during creation HWND hwndButton = CreateWindowEx( 0, L"BUTTON", // Predefined class; Unicode assumed L"OK", // Button text WS_TABSTOP | WS_VISIBLE | WS_CHILD |...

C++17

How do I create a button in C++

26 May 2019 by CPallini

It looks your trying to use a port of the BGI library to Windows. Here you may find documentation and smple code: Borland Graphics Interface (BGI) Documentation[^].

C++17

New to programming...(help? )

14 Jun 2019 by da.ko

Where should I start if I want to learn in a hands-on capacity. I know a bit of c++ syntax but I don't know how to use c++ with a GUI. What project should I start with to learn through hands-on research and trial and error? What I have tried: This. Plus all these extra chars so I am over thirty.

C++17

New to programming...(help? )

14 Jun 2019 by altomaltes

As a low entropy IDE, you can try code::blocks Just install it and do File->new->project->win32 gui project Choose C++ when asked. This will create a minimal debuggable c++ project. Stepping and breakpointing it can help to understand. I don´t advice Visual Studio because is more about Microsoft...

C++17

Error LNK2019: unresolved external symbol on phidgets code

31 Mar 2020 by Member 14162950

I am trying to build a C++ example program from the Phidgets company website that monitors and logs three devices. Using either VS2017 or VS2019 gives 20 lines of messages similar to this one: Log_Mul_Phids(C17_9).obj : error LNK2019: unresolved...

C++17

VS2019

Winsocket keeps disconnecting as soon as it connects

25 Apr 2020 by WOLF 2018

I am working of a DLL for a test and i keep getting socket errors. i am trying to to connect to a server localhost, when it connects i close the server and i want it to continue to try and connect but as i open the server again it keeps...

Winsocket keeps disconnecting as soon as it connects

25 Apr 2020 by User 11060979

Because IsExit is global (whyever) you need to set it to false each time before the loop, otherwhise IsExit reamains true after calling Networking once: ... // while loop to send and receive data IsExit= false; while (!IsExit) { ... }

Winsocket keeps disconnecting as soon as it connects

25 Apr 2020 by WOLF 2018

Ok i found the problem std::string GetData(SOCKET sock) { char buf[1024]; int bytesReceived = recv(sock, buf, 1024, 0); if (bytesReceived == SOCKET_ERROR) std::cout

C/C++: Allocate Variable-size Arrays on the Stack

24 May 2020 by Shao Voon Wong

How to allocate variable-size arrays on the Stack in C/C++

C++17

Why I am not able to declare the class in this program.

15 Dec 2020 by alex bottom122323

I want to try making classes and objects but it's giving me some errors which I am not able to resolve. Below is my code: #include using namespace std; class employee{ int count; int id; public: void set(void){ ...

C++17

C++

Kick start 2021 round C

23 May 2021 by OriginalGriff

While we are more than willing to help those that are stuck, that doesn't mean that we are here to do it all for you! We can't do all the work, you are either getting paid for this, or it's part of your grades and it wouldn't be at all fair for...

C++17

Kick start 2021 round C

23 May 2021 by Patrice T

Quote: Kick start 2021 round C Your problem is that your code is not related to Google's problem. Your task is to write code solving the requirement. The word 'problem' in Google's problem is a requirement, the word 'problem' in your code is...

C++17

Check if linked list is palindrome or not.

6 Jun 2021 by OriginalGriff

Compiling does not mean your code is right! :laugh: Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email...

C++17

C++

DSA

Best way to debug a C++ DLL in release mode

3 Aug 2021 by steveb

You can include debug information in the release build. It will behave as if it was debug build, i.e. stepping through code, breakpoints in code etc.

C++17

VS2019

I am unable to change the bitmap images dispayed on an outlookbar style propertysheet

20 Oct 2021 by Rick York

Yes, KarstenK is correct. If I were you, I would preload all the bitmaps and maintain handles to them. Then when the selection changes building your list will be very fast because you don't have to load any of them. You can just assemble the...

C++17

MFC

Win32

Expression must have a constant value. However, putting constant value doesn't change anything

25 Oct 2021 by shadi zgheib

I keep receiving an error saying "Expression must have a constant value the value of variable 'n1' cannot be used as a constant ". I don't know what am I use suppose to do to fix it. void merge(DataType theArray[], int first, int mid, int last)...

C++17

C++

Expression must have a constant value. However, putting constant value doesn't change anything

25 Oct 2021 by Patrice T

void merge(DataType theArray[], int first, int mid, int last) // did you forgot the '{' here ? int i, j, k; int n1 = mid - first + 1; int n2 = last - mid; int L1[n1], R1[n2]; //n1, n2 are giving me the same problem mentioned above for (i =...

C++17

C++

How do I answer this?

18 Nov 2021 by OriginalGriff

Firstly, there is no obvious connection between the input and the desired output - so go back to the original assignment, and read it carefully. Then try to process the input manually and generate the output - hwne you hav eit manually, it should...

C++17

How do I answer this?

18 Nov 2021 by KarstenK

You best start with some Learn C tutorial to learn the basic. Pay attentation how to use the debugger. Without the knowledge and skills to develop code you cant move on and will get a bad rating from your teacher. tip: also search on Youtube...

C++17

Can someone explains me what does while loop do in this piece of code? I mean oroperator is used but what is the condition fror operator ? LINKEDLIST

14 Dec 2021 by OriginalGriff

You understand OR, I assume? a || b is true is either a, b, or both is true: it is only false if both a and b are both false. And in C (and so C++) any non-zero value is true, so any valid link in l1 or l2 or carry will mean the loop goes around...

C++17