Access Specifier

• public
• private
• protected

public can be access outside of the class.

private can be accessed only from inside the class.

protected cannot be accessed from outside of the class but, can be accessed inherited class.

Example : 1

#include <iostream>
using namespace std;

class Student
{
  public:
  int marks;

  void show()
  {
      cout<<"Marks : "<<marks<<endl;
  }
};
int main() {
    Student s;

    s.name = "ABC";
    s.age = 12;

    s.show();
    return 0;
}

Output :

Name: ABC
Age: 12

Example 2:

#include <iostream>
using namespace std;

class Student
{
  public:
  string name;
  int age;

  void show()
  {
      cout<<"Name: "<<this->name<<endl;
      cout<<"Age: "<<this->age;
  }
};
int main() {
    Student s;

    s.age = 12;

    s.show();
    return 0;
}

Output :

Name:
Age: 12

This

It is a special keyword which stores address of instance current class.

Example :

#include <iostream>
using namespace std;

class Student
{
  public:
  string name;
  int age;
  int fees;

  void show()
  {
      cout<<"Name: "<<this->name<<endl;
      cout<<"Age: "<<this->age<<endl;
      cout<<"Fees: "<<this->fees;
  }
};
int main() {
    Student s;

    s.name = "ABC";
    s.age = 12;
    s.fees = 1000;

    s.show();
    return 0;
}

Output :

Name: ABC
Age: 12
Fees: 1000

Example :

#include <iostream>
using namespace std;

class Student
{
  private:
    string name;
    int age;
    int fees;

  public:
  void getData()
  {
      cout<<"Enter name &  age: ";
      cin>>this->name>>this->age;
  }
  void show()
  {
      cout<<"Name: "<<this->name<<endl;
      cout<<"Age: "<<this->age<<endl;
      cout<<"Fees: "<<this->fees;
  }
};
int main() {
    Student s;

    s.getData();

    s.show();
    return 0;
}

Output :

Enter name & age: Suraj 22
Name: Suraj
Age: 22
Fees: 0

Example :

#include <iostream>
using namespace std;

class Student
{
  private:
    string name;
    int age;
    int fees;

  public:
  void getData()
  {
      cout<<"Enter name &  age: ";
      cin>>this->name>>this->age;
  }
  void show()
  {
      cout<<"Name: "<<this->name<<endl;
      cout<<"Age: "<<this->age<<endl;
      cout<<"Fees: "<<this->fees;
  }
  void payFees()
  {
      cout<<"How much fees you want to pay: ";
      cin>>this->fees;
  }
};
int main() {
    Student s;

    s.getData();
    s.payFees();
    s.show();
    return 0;
}

Output :

Enter name & age: Suraj 22
How much fees you want to pay: 500
Name: Suraj
Age: 22
Fees: 500

Example :

#include <iostream>
using namespace std;

class Student
{
  private:
    string name;
    int fees;

  public:
  void getData()
  {
      cout<<"Enter name: ";
      cin>>this->name;
  }
  void show()
  {
      cout<<"Name: "<<this->name<<endl;
      cout<<"Fees: "<<this->fees<<endl;
  }
  void payFees()
  {
      cout<<"How much fees you want to pay: ";
      cin>>this->fees;
  }
};
int main() {
    Student s;

    s.getData();
    s.payFees();
    s.show();
    return 0;
}

Output :

Enter name: Suraj
How much fees you want to pay: 21
Name: Suraj
Fees: 21