foo.cc: In function 'std::ostream& operator<<(std::ostream&, const Persons&)':
foo.cc:127:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Person>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  127 |   for(int i=0; i<Pes.Arr.size(); i++)
      |                ~^~~~~~~~~~~~~~~
foo.cc: In function 'std::istream& operator>>(std::istream&, Persons&)':
foo.cc:134:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Person>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  134 |   for(int i=0; i<Pes.Arr.size(); i++)
      |                ~^~~~~~~~~~~~~~~

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