foo.cc: In function 'int main()':
foo.cc:8:22: 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.length()-2;i++){
      |                     ~^~~~~~~~~~~~~~
foo.cc:20:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |                         for(int i=0;i<=s.length()-2;i++){
      |                                     ~^~~~~~~~~~~~~~
foo.cc:29:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |                         for(int i=0;i<=s.length()-2;i++){
      |                                     ~^~~~~~~~~~~~~~

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