foo.cc: In function 'std::vector<std::vector<int> > get_map(std::vector<std::vector<int> >)':
foo.cc:10:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |  for (int i = 0;i < map.size();i++)
      |                 ~~^~~~~~~~~~~~
foo.cc:12:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |   for (int j = 1;j < map[0].size();j++)
      |                  ~~^~~~~~~~~~~~~~~
foo.cc:17:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |  for (int i = 1;i < map.size();i++)
      |                 ~~^~~~~~~~~~~~
foo.cc:19:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |   for (int j = 0;j < map[0].size();j++)
      |                  ~~^~~~~~~~~~~~~~~

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