foo.cc: In function 'std::vector<int> add(std::vector<int>, std::vector<int>)':
foo.cc:12:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         for (int i = 0; i < a.size(); i++)
      |                         ~~^~~~~~~~~~
foo.cc:15:23: 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];
      |                     ~~^~~~~~~~~~
foo.cc: In function 'std::vector<int> fun(std::vector<int>)':
foo.cc:28:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         for (int i = 0; i < a.size(); i++) t += a[i];
      |                         ~~^~~~~~~~~~

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