C++11新特性（四）static_assert, share_ptr, unique_ptr简单使用

// auto also as the type of turn, as long as appoint the type

#include <iostream>

auto add(int a,int b)->int

{

   return a + b;

}

int main()

{

    

    static_assert(444 <9000, "too bigger");

    

   auto result = add(1000,200);

   std::cout << result <<std::endl;

    

    

    /*Section of the shared_ptr*/

    

   std::shared_ptr<int> ptr(newint(100));

   std::cout << *ptr <<std::endl;

    

   std::shared_ptr<int> other = ptr;

    *other =200;

   std::cout << *ptr <<std::endl;

    

   auto value = std::make_shared<int>(300);

   std::cout << *value <<std::endl;

    

    /*Section of the unique_ptr*/

    

    std::unique_ptr<int> pn1(newint(2));

    std::unique_ptr<int> pn2 = std::move(pn1);// transfer ownership

   if (!pn1) {

        std::cout <<"It is null" << std::endl;

    }

    

    

    /*Section of the weak_ptr*/

   auto p = std::make_shared<int>(33);

    std::weak_ptr<int> wp = p;

    

    {

       auto sp = wp.lock();

        std::cout << *sp << std::endl;

    }

    

    p.reset();

    

   if(wp.expired())

        std::cout <<"expired" << std::endl;

   return 0;

}