//
// Created by andrew on 2020年11月26日.
//
#include <iostream>

using namespace std;

class Strategy {

public:
 virtual void crypt() = 0;

 virtual ~Strategy() = default;
};

class AES : public Strategy {
public:
 void crypt() override {
 cout << "AES strategy" << endl;
 }
};

class DES : public Strategy {
public:
 void crypt() override {
 cout << "DES strategy" << endl;
 }
};


class Context {
public:
 void setStrategy(Strategy *pStrategy) {
 this->strategy = pStrategy;
 }

 void myOperator() {
 strategy->crypt();
 }

private:
 Strategy *strategy;
};

int main(int argc, char *argv[]) {
 Strategy *strategy = nullptr;

 strategy = new AES;
 Context *context = new Context;
 context->setStrategy(strategy);
 context->myOperator();

 delete strategy;
 delete context;

 return 0;
}