foo.cc: In function 'std::vector<int> subct(std::vector<int>&, std::vector<int>&)':
foo.cc:23:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     for(int i = 0; i < A.size(); i++){
      |                    ~~^~~~~~~~~~
foo.cc:25:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |      if(i<B.size()) t-=B[i];
      |         ~^~~~~~~~~

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