foo.cc: In function 'int main()':
foo.cc:37:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |  for(int i=0;i<c.size();i++)
      |              ~^~~~~~~~~
foo.cc:38:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |   for (int j = 0; j < c.size() - i - 1; j++)
      |                   ~~^~~~~~~~~~~~~~~~~~
foo.cc:45:20: 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 < c.size(); i++)
      |                  ~~^~~~~~~~~~

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