foo.cc: In function 'int main()':
foo.cc:30:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |   for (int i = 0; i != words.size(); i++)
      |                   ~~^~~~~~~~~~~~~~~
foo.cc:45:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |  for (int i = 0; i < words.size(); i++)
      |                  ~~^~~~~~~~~~~~~~
foo.cc:47:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |   for(int j=0;j<words.size()-i-1;j++)
      |               ~^~~~~~~~~~~~~~~~~
foo.cc:56:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |  for (int i = 0; i < words.size(); i++)
      |                  ~~^~~~~~~~~~~~~~

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