Trending questions in C++

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Cases of static and dynamic binding in C++

When an object's static type is used to associate it with a member function, this is known as static binding (understand the type of its class). When a pointer or reference is associated with a member function based on the dynamic type of the object, this is known as dynamic binding (understand the instance of the variable at runtime). Before continuing, keep in mind that dynamic binding only works with pointers, references, and virtual functions for the base class. Because everything needed to call the function is known at compile time, the first call is a static binding (also known as early binding). Derived1 d1(1, 10); d1.display_data(); You already know that the d1 instance is a Derived1 automatic variable, and that it will call the Derived1::display data method (). The first condition is incorrect: d1 is neither a pointer nor a reference. The second condition isn't acceptable:  There is no virtual Derived1::display data. The second call is for ...READ MORE

Jun 7, 2022 in C++ by Damon
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functions in c++ call by value and call by reference

Calling a function by value copies the argument and stores it in a local variable for use by the function, so the argument is unaffected if the value of the local variable changes.  The argument is passed to the function as a reference rather than a copy, so if the function changes the value of the argument, the argument is also changed.   The void change(int); function prototype informs the compiler that there is a function named change that takes a single int argument and returns void (i.e. nothing).  Because there is no & with the argument, it is called by value.  You have the line change(orig); later in your code, which actually calls the function with. Take a look at the output of ...READ MORE

Jun 7, 2022 in C++ by Damon
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Intersection of two std::unordered_map

I have two std::unordered_map std::unordered_map<int, int> mp1; std::unordered_map<int, int> ...READ MORE

May 31, 2022 in C++ by Nicholas
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Function default argument value depending on argument name in C++ [duplicate]

When the function is called with no argument for the corresponding parameter, the default argument is evaluated.  In a default argument, a parameter must not appear as a potentially evaluated expression.  A function's parameters declared before a default argument are in scope and can obscure the namespace and class member name. It provides the following example: int h(int a, ...READ MORE

Jun 7, 2022 in C++ by Damon
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When to use virtual destructors?

When you want to delete an instance of a derived class using a pointer to the base class, virtual destructors come in handy: class Base { // ...READ MORE

Jun 7, 2022 in C++ by Damon
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What data structure is inside std::map in C++?

An associative container is std::map. The standard's ...READ MORE

May 31, 2022 in C++ by Damon
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static memory allocation like dynamic memory allocation

int r, c; cin >> r >> c; int ...READ MORE

Jun 6, 2022 in C++ by Nicholas
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functions in c++ call by value and call by reference

The code below shows how to call a function in both methods.  Please explain the major differences or meanings of call by value and call by reference to me.  1.Make a value-based call.  2.Call based on a reference.  The call by value method is demonstrated in the following code. In a comment, I expressed my reservations. #include<iostream> int main(){ void change(int);//why function prototype is before ...READ MORE

Jun 6, 2022 in C++ by Nicholas
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Code Not working in VS Code but works in OnlineGDB

I am practicing about primeSieve with C++ language in VS Code 1.57.1. Can ...READ MORE

Jun 1, 2022 in C++ by Nicholas
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How can I convert a std::string to int?

There are some new convert methods in C++ that convert std::string to a numeric type. As an alternative to str.c str() atoi(str.c str()) atoi(str.c str() you can make use of std::stoi std::stoi ...READ MORE

Jun 1, 2022 in C++ by Damon
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The new syntax "= default" in C++11

A defaulted default function Object() { [native code] } is defined as a user-defined default function Object() { [native code] } with an empty compound statement and no initialization list. I'll give you an example to demonstrate the difference: #include <iostream> using namespace std; class A { public: ...READ MORE

Jun 7, 2022 in C++ by Damon
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Use of min and max functions in C++

Are std::min and std::max better than fmin ...READ MORE

Jun 2, 2022 in C++ by Nicholas
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C++ "Object" class

No, there is no generic base class&nb ...READ MORE

Jun 2, 2022 in C++ by Damon
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What is a smart pointer and when should I use one?

A smart pointer is similar to a ...READ MORE

Jun 2, 2022 in C++ by Damon
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559 views
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How to reverse an std::string?

A reverse function is integrated into C++ and can be used to reverse a string.  This function accepts two parameters: The start iterator for the string The string iterator has come to an end. The following line of code demonstrates how to use this function: #include <iostream> //The library below must be included ...READ MORE

Jun 1, 2022 in C++ by Damon
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How to implement 2D vector array?

I'm using the vector class in the ...READ MORE

Jun 1, 2022 in C++ by Nicholas
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638 views
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Syntax of priority queue

We must first include the queue header file in order to establish a priority queue in C++. #include <queue> Once we import this file, we ...READ MORE

May 31, 2022 in C++ by Damon
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700 views
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What is the C++ function to raise a number to a power?

What's the best way to raise a n ...READ MORE

Jun 1, 2022 in C++ by Nicholas
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C++ `this` pointer

Pointer variables are used to store the ...READ MORE

May 31, 2022 in C++ by Damon
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658 views
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Declare abstract class in c++

An abstract class is one that is intended to be used as a base class .  At least one pure virtual function exists in an abstract class.  A pure virtual function is declared in the class declaration by using a pure specifier (= 0) in the declaration of a virtual member function. Here is an example of an abstract class: class AB { public: virtual void f() ...READ MORE

May 31, 2022 in C++ by Damon
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Constructor Overloading in C++

My C++ overloading does not work as I expect it to: #include "Node.h" #include <iostream> Node::Node() { cout ...READ MORE

Jun 2, 2022 in C++ by Nicholas
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451 views
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How to implement 2D vector array?

I'm using the vector class in the ...READ MORE

Jun 1, 2022 in C++ by Nicholas
• 7,760 points
457 views