Step by Step solution about How to resolve the algorithm Enforced immutability step by step in the C++ programming language

The provided code demonstrates the use of class member functions and constructors in C++. Let's break down the code step by step:

1. Class Declaration:

   • Two classes are defined in the code: MyOtherClass and MyClass.

2. MyOtherClass:

   • It has a single public member variable m_x.
   • It has a constructor that takes an optional argument initX with a default value of 0. This constructor initializes m_x with either the provided value or the default value of 0.

3. MyClass:

   • It has a private member variable x.
   • It has a public member function getX() that is declared as const, which means it cannot modify the object's state. getX() returns the value of x.

4. main Function:

   • It creates two instances of MyOtherClass, mocA and mocB.
   • It sets the value of mocB's m_x to 7 using the constructor.
   • It prints the values of mocA.m_x and mocB.m_x, which are 0 and 7, respectively.
   • It attempts to modify mocB.m_x directly (which is commented out), but it will fail because m_x is a const member and cannot be modified.

The key concepts illustrated in this code are:

• Class constructors: Constructors are used to initialize objects when they are created and can have optional arguments with default values.
• Const members: Const members cannot be modified after the object is created, ensuring data integrity.
• Const member functions: Const member functions cannot modify the object's state, making them suitable for accessing data without side effects.

#include <iostream>

class MyOtherClass
{
public:
  const int m_x;
  MyOtherClass(const int initX = 0) : m_x(initX) { }

};

int main()
{
  MyOtherClass mocA, mocB(7);

  std::cout << mocA.m_x << std::endl; // displays 0, the default value given for MyOtherClass's constructor.
  std::cout << mocB.m_x << std::endl; // displays 7, the value we provided for the constructor for mocB.

  // Uncomment this, and the compile will fail; m_x is a const member.
  // mocB.m_x = 99;

  return 0;
}


class MyClass
{
private:
    int x;
  
public:
    int getX() const
    {
        return x;
    }
};