foo.cc: In function 'int main()':
foo.cc:7:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    7 |         for(int i = 0; i < s.size(); i++){
      |                        ~~^~~~~~~~~~
foo.cc:10:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for(int i = 0; i < s.size(); i++){
      |                        ~~^~~~~~~~~~
foo.cc:11:38: 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 j = i + 1; j < s.size(); j++){
      |                                    ~~^~~~~~~~~~
foo.cc:20:26: 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.size(); i++){
      |                        ~~^~~~~~~~~~

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