//Singleton.h

#include <iostream>
using namespace std;

class Singleton
{
private:
    static Singleton *minstance;
    Singleton();
public:
    static Singleton *getInstance();
};

//Singleton.cpp

Singleton::Singleton()
{
    cout<<"private construct singleton"<<endl;
}

Singleton* Singleton::minstance =NULL; //必须在此处声明，否则报错

Singleton * Singleton::getInstance()
{
    if (minstance==NULL)
    {
        minstance=new Singleton();
    }
    
    return minstance;
}

//main.cpp
#include "Singleton.h"

void main()
{
    Singleton* singleton1 = Singleton::getInstance();
    Singleton* singleton2 = Singleton::getInstance();

    if (singleton1 == singleton2)
        fprintf(stderr,"singleton1 = singleton2\n");


    return;

}