foo.cc: In function 'void Add(std::vector<int>&, std::vector<int>&, std::vector<int>&)':
foo.cc:23:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for(i=0; i<a1.size() && i<a2.size() ; i++)
      |                  ~^~~~~~~~~~
foo.cc:23:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for(i=0; i<a1.size() && i<a2.size() ; i++)
      |                                 ~^~~~~~~~~~
foo.cc:28:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         for(; i<a1.size(); i++)
      |               ~^~~~~~~~~~
foo.cc:33:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |         for(; i<a2.size(); i++)
      |               ~^~~~~~~~~~
foo.cc: In function 'void Mul(std::vector<int>&, std::vector<int>&, std::vector<int>&)':
foo.cc:45:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         for(int i=0; i<a1.size(); i++)
      |                      ~^~~~~~~~~~
foo.cc:46:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |                 for(int j=0; j<a2.size(); j++)
      |                              ~^~~~~~~~~~
foo.cc:51:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |         for(int i=0; i<a3.size(); i++)
      |                      ~^~~~~~~~~~

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