foo.cc: In function 'int main()':
foo.cc:8:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |         for (int i = 0; i < s.size() - 1; i++)
      |                         ~~^~~~~~~~~~~~~~
foo.cc:15:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |                 for (int i = 0; i < s.size(); i++)
      |                                 ~~^~~~~~~~~~
foo.cc:21:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |                 for (int i = 0; i < s.size()-1; i++)
      |                                 ~~^~~~~~~~~~~~

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