foo.cc: In function 'std::vector<int> add(std::vector<int>&, std::vector<int>&)':
foo.cc:13:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |  for(int i = 0; i < A.size(); i++){
      |                 ~~^~~~~~~~~~
foo.cc:15:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |   if(i < B.size()) t+= B[i];
      |      ~~^~~~~~~~~~

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