#include <iostream>
#include <string>
#include <vector>

using namespace std;

class Flyweight {
public:
 Flyweight(string state):_state(state) {

 }

 virtual void Operation(const string&state) { }

 string GetState()const { return _state; }

 virtual ~Flyweight() { }
private:
 string _state;
};

class ConcreteFlyweight :public Flyweight {
public:
 ConcreteFlyweight(string state)
 :Flyweight(state) {
 cout << "ConcreteFlyweight Build..." << state << endl;
 }

 void Operation(const string& state) {
 cout << "ConcreteFlyweight " << GetState() << " \\ " << state << endl;
 }
};

class FlyweightFactory {
public:
 Flyweight *GetFlyweight(std::string key) {
 for (auto fly : _flys) {
 if (fly->GetState() == key) {
 cout << "already created by users..." << endl;
 return fly;
 }
 }
 Flyweight *fn = new ConcreteFlyweight(key);
 _flys.push_back(fn);
 return fn;
 }
private:
 std::vector<Flyweight*> _flys;
};

int main() {
 FlyweightFactory *fc = new FlyweightFactory();
 Flyweight *fw1 = fc->GetFlyweight("hello");
 Flyweight *fw2 = fc->GetFlyweight("world");
 Flyweight *fw3 = fc->GetFlyweight("hello");

 delete fw1;
 delete fw2;
 //delete fw3;
 delete fc;

 return 0;
}