【C++代码】之《单例模式》

#include <iostream>
using namespace std;

class Singleton
{
private:
    static Singleton* instance;
    Singleton() {};

public:
    static Singleton* GetInstance()
    {
        if (instance == nullptr)
        {
            instance = new Singleton;
        }
        return instance;
    }
};

// 静态成员变量的初始化在类的外部
Singleton* Singleton::instance = nullptr;

int main()
{
    Singleton* p1 = Singleton::GetInstance();
}