text: //Remember:模板是用来产生类型的
  
  #include <iostream>
  #include <vector>
  #include <map>
  
  using namespace std;
  
  template<typename... Ts>class Magic{};
  
  template<typename... Args> void printf(const string &str, Args... args);
  
  template<typename... Args> void magic(Args... args){
      cout << sizeof...(args) << endl;
  }
  
  int main(){
      class Magic<> nothing;
      class Magic<int, double, map<int, vector<int>>> darkMagic;
  
      magic();
      magic(1.0);
      magic("str",2);
  
      
  }