text: #include <iostream>
  #include <string>
  
  #include "../user/User.cpp"
  
  using namespace std;
  
  int main()
  {
      // std::string str = "this is string";
      string str("ss");
      int size = str.size();
  
      double array[3] = {0.1, 0.2, 0.3};
  
      User u1;
  
      u1.age = 12;
      u1.name = "xiang wen shan";
      u1.email = "id512@126.com";
      std::cout << "Hello, World!" << u1.name <<" age is " << u1.name << std::endl;
      cout << "print str = " << str << endl;
      for (int i = 0; i < sizeof(array); i++)
      {
  
          printf("this is print %d %f\n", i, array[i]);
      }
  
      return 0;
  }