foo.cc: In function 'void Add(std::vector<int>&, std::vector<int>&, std::vector<int>&)':
foo.cc:41:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |         for(i=0;i<v1.size() && i<v2.size();i++)
      |                 ~^~~~~~~~~~
foo.cc:41:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |         for(i=0;i<v1.size() && i<v2.size();i++)
      |                                ~^~~~~~~~~~
foo.cc:47:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |         for(;i<v1.size();i++)
      |              ~^~~~~~~~~~
foo.cc:53:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |         for(;i<v2.size();i++)
      |              ~^~~~~~~~~~
foo.cc: In function 'void Mul(std::vector<int>&, int)':
foo.cc:65:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |         for(int i=0;i<v.size();i++)
      |                     ~^~~~~~~~~

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