#include <memory>

#include <iostream>

using namespace std;

class Widget{

public:

void print(){

cout << "Widget" << endl;

}

};

template <class T> class SmartPtr{

public:

template<typename U> SmartPtr(const SmartPtr<U>& other):heldPtr(other.get()){}

T* get() const { return heldPtr;}

private:

T* heldPtr;

};

struct ArrNode{

int val;

ArrNode *next;

};

/***

* 模版元编程

* 在编译期间，完成代码执行

* ***/

template<unsigned n> struct Factorial{

enum{value = n*Factorial<n-1>::value};

};

// 特殊情况

template<> struct Factorial<0>{

enum{value = 1};

};

// operator new 是自己写一个new和一个delete也可以写

class Midget{

public:

static new_handler set_new_handler(new_handler p) throw();

static void* operator new(size_t size) throw(bad_alloc);

static void* operator delete(size_t size) throw(bad_alloc);

private:

static new_handler currentHandler;

};

void* Midget::operator new(size_t size) throw(bad_alloc){

::operator new(size);

return;

}

new_handler Midget::currentHandler = 0;

int main(){

// shared_ptr<string> sptr = make_shared<string>("hello");

// //*sptr = "hello,world!";

// cout << *sptr << endl;

// shared_ptr<Widget> wptr;

// wptr->print();

// // SmartPtr<Widget> smaPtr(Widget);

// int *arr[10];

// int iNum = 10;

// arr[1] = &iNum;

// cout << *arr << endl;

// char ctr = 'a';

// int a = ctr%15;

// cout << a << endl;

// ArrNode *arrNode[4];

// arrNode[0]->val = 42;

// cout << arrNode[0]->val << endl;

enum enumType{Mon,Tue,Wed,Thur,Fri,Sat,Sun} Weekday;

Weekday = enumType(3);

cout << Weekday << endl;

cout << Factorial<5>::value<<endl;

return 0;

}