zainulabidin302

class AbstractClassExample {
	public: 
  		virtual int dieHard()=0;
};

class YetAnotherAbstractClassExample: public AbstractClassExample {};

class FinallyConcreteClassExample: public AbstractClassExample {
	public: 
  		int dieHard() {

zainulabidin302

class Device { };
class Tablet : public Device{};
class Iphone : public Device{};
class Mobile : public Device{};

class Person {
	
  	//Iphone device; rahter then concrete implementation we are using interface
  	Device * device;
  public:

zainulabidin302

#include <iostream>
using namespace std;

class ConfigurationManager {
 private: 
  ConfigurationManager(){
  }
  
 public:
  static ConfigurationManager & getInstance() {