foo.cc: In function 'int main()':
foo.cc:29:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |  for(int i = 0;i<va.size();i++)
      |                ~^~~~~~~~~~
foo.cc:32:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |   for(;j<vb.size();j++)
      |        ~^~~~~~~~~~
foo.cc:36:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |   if(j == vb.size()) vc.push_back(va[i]);
      |      ~~^~~~~~~~~~~~
foo.cc:39:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |  for(int i = 0;i<vc.size();i++)
      |                ~^~~~~~~~~~

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