Question

show the general form new and delete operator in c++​

Answer 1

Explanation:

In this program, we are going to learn about new and delete operators in C++ programming language, and testing the case of calling constructor and destructors while allocating and deal locating the memory dynamically.

Submitted by IncludeHelp, on May 22, 2018

In C++ programming language, there are two operators 1) new and 2) delete, which are used to manage the memory dynamically i.e. to create, delete the memory at run time (dynamically)

Prerequisite: new and delete operators in C++ programming

Let’s understand, when 'new' and 'delete' are used?

new is used to declare memory blocks at run time (dynamically). While, delete is used to delete/free the memory which has been declared dynamically.

Example of new and delete in C++

In the given program, we are using new to allocate memory to the class object and delete/free is using to delete the reference of the pointer that will force. There is a class named sample and it has a constructor sample() and a destructor ~sample().

Consider the program:

#include <iostream>

using namespace std;

class sample

{

    public:

sample()

{

cout<<"Hi ";

}

~sample()

{

cout<<"Bye ";

}

};

int main()

{

sample *obj = new sample();

delete(obj);

return 0;

}

Output

Hi Bye

You can see, "Hi" is written in the constructor (sample()) while "Bye" is written in the destructor (~sample()).

Therefore, when object "obj" is creating, constructor will be called and print "Hi", same as when object is going to be freed using delete(obj), destructor (~sample()) will be called and print "Bye".