5.decltype类型拷贝

 #include <iostream>
 using namespace std;

 template <class T>
 void show(T *p)
 {
     //初始化
     decltype(*p) num(*p);
     cout << *p << endl;
 }

 void main()
 {
     auto man("");
     cout << typeid(man).name() << "           " << man << endl;
     auto man2(man);
     cout << typeid(man2).name() << "           " << man << endl;

     //获取变量类型,创建类型或指针,并初始化
     decltype(man) man3[]{ man,man };
     for (auto i : man3)
     {
         cout << typeid(i).name() << "           " << i << endl;
     }

     int num = ;
     show(&num);
     cin.get();
 }