Latest questions in C++

0 votes
0 answers

Is there a maxheap in the C++ standard library?

I understand that the std::priority queue class ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
977 views
0 votes
0 answers

how to print \" in C++

I need to print the following string: std::string("-I\"/path/to/dir\" "); Basically, I need to accomplish this since I am generating C++ code using C++ code. I want to use an ofstream to write the above string, so something like ofstream fout; fout << the_string ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
726 views
0 votes
0 answers

Efficient way to return a std::vector in c++

When delivering a std::vector in a function, how much data is duplicated, and how much of an optimization will it be to place the std::vector in free-store (on the heap) and provide a pointer instead, i.e. is: std::vector *f() { std::vector *result = new ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
748 views
0 votes
0 answers

std::cin input with spaces?

#include <string> std::string input; std::cin >> input; The user want to type "Hello World."  However, cin fails to recognise the space between the two words.  How do I get Cin to see the entire Hello World? I'm trying this using structs, and cin.getline doesn't appear to work.  This is my code: struct cd { ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
1,177 views
0 votes
0 answers

In C, are arrays pointers or used as pointers?

First, look at this code When this is ...READ MORE

Aug 11, 2022 in C++ by krishna
• 2,820 points
805 views
0 votes
0 answers

How to generate a random number in C++?

I'm attempting to develop a dice game, and I need random numbers to represent the sides of the die.  I can make a number between 1 and 6).  Using #include <cstdlib> #include <ctime> #include <iostream> using namespace ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
698 views
0 votes
0 answers

declaring a priority_queue in c++ with a custom comparator

I'm attempting to declare a priority queue of nodes using the comparator function bool Compare(Node a, Node b) (which is outside the node class). I presently have the following: priority_queue<Node, vector<Node>, Compare> openSet; I'm receiving Error: "Compare" is not a type name for some reason. Adding priority_queue<Node, vector Node>, bool Compare> to the declaration. gives me the error 'Error: expecting a '>' I've also attempted: priority_queue<Node, vector<Node>, Compare()> openSet; priority_queue<Node, ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points
1,292 views
0 votes
0 answers

Confused with object arrays in C++

I have some Java knowledge and now ...READ MORE

Aug 11, 2022 in C++ by krishna
• 2,820 points
461 views
0 votes
0 answers

Is C++ considered weakly typed? Why?

C++ has always struck me as one ...READ MORE

Aug 8, 2022 in C++ by Nicholas
• 7,760 points
2,109 views
0 votes
0 answers

Difference between 'struct' and 'typedef struct' in C++?

In C++, is there any difference between: struct Foo ...READ MORE

Aug 8, 2022 in C++ by Nicholas
• 7,760 points
984 views
0 votes
0 answers

How do you properly use namespaces in C++?

I come from a Java background where ...READ MORE

Aug 8, 2022 in C++ by Nicholas
• 7,760 points
808 views
0 votes
0 answers

What are Containers/Adapters? C++

What exactly are containers/adapters? I am familiar ...READ MORE

Aug 8, 2022 in C++ by Nicholas
• 7,760 points
772 views
0 votes
0 answers

How do you open a file in C++?

I want to open a file in ...READ MORE

Aug 8, 2022 in C++ by Nicholas
• 7,760 points
710 views
0 votes
0 answers

How come an array's address is equal to its value in C?

The pointer values and pointer addresses in ...READ MORE

Aug 8, 2022 in C++ by krishna
• 2,820 points
589 views
0 votes
0 answers

How can I get the size of a C++ function?

In C++, how can I find the size& ...READ MORE

Aug 5, 2022 in C++ by Nicholas
• 7,760 points
811 views
0 votes
0 answers

Nested try...catch inside C++ exception handler?

I may wish to run code that might throw an exception in my exception handler. Is the following C++ structure acceptable?  Are there any drawbacks if so? try { // ... } catch (const ...READ MORE

Aug 5, 2022 in C++ by Nicholas
• 7,760 points
798 views
0 votes
0 answers

How can I get double quotes into a string literal?

I used the printf() command to produce the output seen below: printf("She said time flies like an arrow, ...READ MORE

Aug 5, 2022 in C++ by Nicholas
• 7,760 points
1,096 views
0 votes
0 answers

std::string length() and size() member functions

While reading the responses to this topic, ...READ MORE

Aug 5, 2022 in C++ by Nicholas
• 7,760 points
1,235 views
0 votes
0 answers

Insert object at index of vector c++

I have to add a new item to the existing object vector.  Although I am aware that an iterator must be used, I am not entirely sure how it operates. I need to insert a new item by name in the precise index that I found after some searching into an alphabetically sorted vector.  I have this, then. vector<Person>people; int index =54; Person temp; people.push_back(temp);//insert at end of ...READ MORE

Aug 5, 2022 in C++ by Nicholas
• 7,760 points
978 views
0 votes
0 answers

How to make an array with a dynamic size? General usage of dynamic arrays (maybe pointers too)?

I wanna create a program that can ...READ MORE

Aug 5, 2022 in C++ by krishna
• 2,820 points
1,195 views
0 votes
1 answer

What's the difference between constexpr and const?

Variables are protected from modification in your ...READ MORE

Aug 5, 2022 in C++ by Damon
• 4,960 points
1,715 views
0 votes
1 answer

How do I create an array of pointers?

Student** db = new Student*[5]; // To allocate ...READ MORE

Aug 5, 2022 in C++ by Damon
• 4,960 points
1,283 views
0 votes
1 answer

Reverse Contents in Array

My strategy would be as follows: #include <algorithm> #include <iterator> int main() { const int ...READ MORE

Aug 5, 2022 in C++ by Damon
• 4,960 points
813 views
0 votes
1 answer

Create a reverse LinkedList in C++ from a given LinkedList

A simpler solution is to just let the current node point to the previous node while going through your linked list, saving the previous and next nodes as you go. void LinkedList::reversedLinkedList() { if(head == ...READ MORE

Aug 5, 2022 in C++ by Damon
• 4,960 points
1,026 views
0 votes
1 answer

Why should I use reference variables at all?

References themselves are unrelated to the issue. The issue is because C++ manages object lifetimes differently from run-time systems that employ garbage collectors, such as Java.  There is no standard built-in garbage collector in C++.  Both automatic (within local or global scope) and manual (explicitly allocated/deallocated in heap) object lifetimes are possible in  C++. A C++ reference is nothing more than an object's alias.  It has no knowledge of object lifespan (for the sake of efficiency).  The coder must give it some thought.  A reference bound to a temporary object is an exception; in this situation, the temporary object's lifespan is prolonged to include the lifetime of the bound reference. References play a crucial role in the fundamental ideas of C++, and they are required for 90% of jobs.  Otherwise, pointers must be used, which is typically far worse. You can use references, for instance, when you need to give an object as a function parameter by reference rather than by value: void f(A copyOfObj); ...READ MORE

Aug 5, 2022 in C++ by Damon
• 4,960 points
881 views
0 votes
1 answer

Socket Programming in C++

The C++ Standard does not have a ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
942 views
0 votes
1 answer

"We do not use C++ exceptions" — What's the alternative? Let it crash?

If you don't utilise exceptions, by definition, ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
642 views
0 votes
1 answer

How to convert an instance of std::string to lower case

#include <algorithm> #include <cctype> #include <string> std::string data = "Abc"; std::transform(data.begin(), ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
2,424 views
0 votes
1 answer

Passing a 2D array to a C++ function

How to pass 2D array to a ...READ MORE

Oct 13, 2023 in C++ by Artp

edited Mar 5 32,039 views
0 votes
1 answer

Examples of good gotos in C or C++

Here's one method I've heard of folks use. But I've never seen it in the wild.  And that only pertains to C since RAII allows you to accomplish this more idiomatically in C++. void foo() { if (!doA()) ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
640 views
0 votes
1 answer

What does Tokens do and why they need to be created in C++ programming?

Tokenization is essential in determining what a programme does.  What Bjarne is referring to in respect to C++ code is how tokenization rules alter the meaning of a programme.  We need to know what the tokens are and how they are determined.  Specifically, how can we recognise a single token when it comes among other characters, and how should tokens be delimited if  there is ambiguity? Consider the prefix operators ++ and +, for example. Assume we have just one token + to deal with.  What does the following excerpt mean? int i = 1; ++i; Is the above going to apply unary + on i twice with + only? Or will it only increase it once? Naturally, it's vague.  We require an additional token, thus ++ is introduced as its own "word" in the language. But there is now another (though minor) issue.  What if the programmer just wants to use unary + twice without incrementing?  Rules for token processing are required.  So, if we discover that a white space is always used as a token separator, our programmer may write: int i ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
1,287 views
0 votes
1 answer

What is the difference between operator overloading and operator overriding in C++?

Some people use the latter word to ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
2,183 views
0 votes
1 answer

Is there any built-in factorial function in c++?

Although no C function is written particularly for computing factorials, the C math package allows you to compute the gamma function. Because (n) Equals (n-1)!  Using tgamma of i+1 on positive integers returns i!. for (int i = 1 ; ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
9,531 views
0 votes
1 answer

What is dynamic initialization of object in c++?

Dynamic initialization occurs when the initialization value is unknown at compile time.  To initialise the variable, it is calculated at runtime. Example, int factorial(int n) { ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
2,436 views
0 votes
1 answer

How do I use 'strlen()' on a C++ string

In C++, there are two standard methods for storing strings.  In this scenario, you specify an array of characters, and 0 signifies the end of the string. #include <cstring> char str[500] = "Hello"; // How ever ...READ MORE

Aug 2, 2022 in C++ by Damon
• 4,960 points
1,471 views
0 votes
0 answers

What are C++ functors and their uses?

I've been hearing a lot about functors ...READ MORE

Aug 1, 2022 in C++ by Nicholas
• 7,760 points

edited Mar 4 80 views
0 votes
0 answers

C - If value in array

I have this goal to check if ...READ MORE

Jul 28, 2022 in C++ by krishna
• 2,820 points

edited Mar 4 70 views
0 votes
0 answers

What is meant with "const" at end of function declaration?

I received a book in which it is written: class Foo { public: int ...READ MORE

Jul 28, 2022 in C++ by Nicholas
• 7,760 points
694 views
0 votes
0 answers

How can i sort a map by its .second parameter

How can I output all the int ...READ MORE

Jul 28, 2022 in C++ by Nicholas
• 7,760 points
958 views
0 votes
0 answers

Check if a string contains a string in C++

I've got a std::string variable. I'd want ...READ MORE

Jul 28, 2022 in C++ by Nicholas
• 7,760 points
765 views
0 votes
0 answers

Container Class vs Class - C++

I'm new to programming and have only ...READ MORE

Jul 28, 2022 in C++ by Nicholas
• 7,760 points
508 views
0 votes
0 answers

How to code a modulo (%) operator in C/C++/Obj-C that handles negative numbers

As a mathematician, one of my pet peeves of C-derived languages is : (-1) % 8 // comes out as ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points
599 views
0 votes
0 answers

What type of members can I add in a c++ abstract class

Hello, let's say I have an abstract class with a few pure abstract functions and a few classes that derive from it, and all of the data from these classes eventually becomes similar, I was wondering if it would be wise, or even possible, to declare a vector under protected in the abstract class to collect the data so something like that. class A { protected: vector <string> ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points
568 views
0 votes
0 answers

What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?

I looked up the differences between cout, ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points
911 views
0 votes
0 answers

Simple C++ swap function

Why is it that if I have a method like this to swap two numbers, it doesn't work[swap], (I know I can accomplish this by defining pointers in the prototype and then passing the addresses of the relevant variables in main()), yet it works for arrays without having to supply pointers and addresses? It does not work. void num_exchange(int m, int n); int main(){ int num1 ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points
585 views
0 votes
0 answers

How to initialize an std::string with a length?

How can I correctly initialise a string if its length is specified at build time? #include <string> int length = 3; string word[length]; //invalid ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points
1,407 views
0 votes
0 answers

How to declare an array of strings in C++?

I am trying to iterate over all ...READ MORE

Jul 26, 2022 in C++ by Nicholas
• 7,760 points
749 views
0 votes
0 answers

What are the new features in C++17?

C++17 is currently feature complete, therefore major ...READ MORE

Jul 26, 2022 in C++ by Nicholas
• 7,760 points
528 views
0 votes
0 answers

Understanding c++ Code: Tower of Hanoi using Recursion

I'm studying about recursion in C++, but the following C++ code used to solve the Tower of Hanoi issue has me baffled. void Hanoi(int m, string start, string middle, ...READ MORE

Jul 26, 2022 in C++ by Nicholas
• 7,760 points
682 views
0 votes
0 answers

Storing C++ template function definitions in a .CPP file

I have some template code that I'd rather have saved in a CPP file rather than inline in the header.  I know this is possible if you know which template types will be utilised.  As an example: .h file class foo { public: template <typename ...READ MORE

Jul 26, 2022 in C++ by Nicholas
• 7,760 points
895 views