/**
 * @name 策略模式
 * @brief: 封装可互换的算法
 * @note 场景：支付方式选择（信用卡/支付宝）、排序算法切换
 */

class PaymentStrategy {
public:
    virtual void pay(int amount) = 0;
};

class CreditCardStrategy : public PaymentStrategy {
    void pay(int amount) override { /* 信用卡支付逻辑 */ }
};

class PaymentContext {
    PaymentStrategy* strategy;
public:
    void setStrategy(PaymentStrategy* s) { strategy = s; }
    void executePayment(int amount) { strategy->pay(amount); }
};

// 使用
int main()
{
    PaymentContext context;
    context.setStrategy(new CreditCardStrategy());
    context.executePayment(100);
    return 0;
}