把要执行的动作包装为对象，可实现动作的延时执行，或撤销

C++引入 lambda表达式 以及函数对象后，这个设计模式存在的意义其实就不大了，了解设计思想即可

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

class Chief {
public:
    void makeGBJD() {
        std::cout << "宫保鸡丁已做好" << std::endl;
    }
    void makeYXRS() {
        std::cout << "鱼香肉丝已做好" << std::endl;
    }
    void makeDCF() {
        std::cout << "蛋炒饭已做好" << std::endl;
    }
};

class AbstructCmd {
public:
    AbstructCmd(Chief* chief) : m_chief(chief) {}
    virtual ~AbstructCmd() {}
    virtual void excute() = 0;
protected:
    Chief* m_chief;
};

class GBJDCmd : public AbstructCmd {
public:
    using AbstructCmd::AbstructCmd;
    void excute() override {
        m_chief->makeGBJD();
    }
};
class YXRSCmd : public AbstructCmd {
public:
    using AbstructCmd::AbstructCmd;
    void excute() override {
        m_chief->makeYXRS();
    }
};
class DCFCmd : public AbstructCmd {
public:
    using AbstructCmd::AbstructCmd;
    void excute() override {
        m_chief->makeDCF();
    }
};

class Waiter {
public:
    void AddCmd(AbstructCmd* cmd) {
        m_cmds.push_back(cmd);
    }

    void Finish() {
        for(auto &item : m_cmds) {
            item->excute();
        }
        m_cmds.clear();
    }
private:
    std::vector<AbstructCmd*> m_cmds;
};

int main() {
    Chief c;
    AbstructCmd* p1 = new GBJDCmd(&c);
    AbstructCmd* p2 = new YXRSCmd(&c);
    AbstructCmd* p3 = new DCFCmd(&c);

    Waiter w;

    w.AddCmd(p1);
    w.AddCmd(p3);
    w.Finish();

    std::cout << "==========================" << std::endl;
    w.AddCmd(p1);
    w.AddCmd(p2);
    w.AddCmd(p3);
    w.Finish();

    return 0;
}