foo.cc: In member function 'void Student::Sort()':
foo.cc:33:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |   for(ll i = 0;i<v.size();i++)
      |                ~^~~~~~~~~
foo.cc:35:20: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |    for(ll j = i+1;j<v.size();j++)
      |                   ~^~~~~~~~~
foo.cc: In member function 'void Student::Output()':
foo.cc:45:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |   for(ll i = 0;i<v.size();i++)
      |                ~^~~~~~~~~

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