foo.cc: In constructor 'Person::Person(int, int, int, int, int, int, std::string)':
foo.cc:23:14: warning: 'Person::dep' will be initialized after [-Wreorder]
   23 |         Date dep;
      |              ^~~
foo.cc:21:16: warning:   'std::string Person::name' [-Wreorder]
   21 |         string name;
      |                ^~~~
foo.cc:25:9: warning:   when initialized here [-Wreorder]
   25 |         Person(int y1, int m1, int d1, int y2, int m2, int d2, string name) :
      |         ^~~~~~
foo.cc: In member function 'void Persons::Output()':
foo.cc:47:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Person*>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |                 for (int i = 0; i < ps.size(); i++)
      |                                 ~~^~~~~~~~~~~
foo.cc: In destructor 'virtual Persons::~Persons()':
foo.cc:52:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Person*>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |                 for (int i = 0; i < ps.size(); i++)
      |                                 ~~^~~~~~~~~~~

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