foo.cc: In function 'int main()':
foo.cc:11:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |     for (int i = 0; i < s.length(); i++)
      |                     ~~^~~~~~~~~~~~
foo.cc:23:23: 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]
   23 |     for (int i = 0; i < words.size(); i++)
      |                     ~~^~~~~~~~~~~~~~
foo.cc:25:23: 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]
   25 |     for (int i = 0; i < words.size(); i++)
      |                     ~~^~~~~~~~~~~~~~

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