In C++ a constructor is a special method of a class or structure in object-oriented programming that initializes a newly created object of that type. Whenever an object is created, the constructor is called automatically. Constructor is used to initializing objects of a class and allocate appropriate memory to objects. That is, it is used to initialize the instance variables of a class with a different set of values but it is not necessary to initialize.

Constructor Types:

• Default Constructor.
• Parameterized Constructor.
• Copy Constructor.
• Static Constructor.
• Private Constructor.

Example Of A Constructor:

#include <iostream>
#include <string>
using namespace std;

class Employee
    {
        public: //private: , protected:
        string name;
        int salary;

        Employee(string n, int s, int sp)
        {
            this->name = n;
            this->salary = s;
            this->secretPassword = sp;
        }

        void printDetails()
    {
        cout<<"The name of our first employee is "<< this->name << " and his salary is " << this->salary<<" dollers"<<endl;
    }
    void getsecretPassword()
    {
        cout<<"The secret password is "<<this->secretPassword<<endl;
    }
    private:
    int secretPassword;
    };
        
    class programmer : public Employee  //inheritance
    {
        public:
        int errors;
    };



int main()
{
    Employee ak("akshat constructor", 3000000, 23334);
    ak.printDetails();
    ak.getsecretPassword();
    return 0;
}

There are no “return value” statements in the constructor, but the constructor returns the current class instance.