foo.cc: In function 'int main()':
foo.cc:7:37: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
    7 |         if(s.find("er", s.size()-2) != -1)
      |            ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
foo.cc:9:42: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
    9 |         else if(s.find("ly", s.size()-2) != -1)
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
foo.cc:11:43: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   11 |         else if(s.find("ing", s.size()-3) != -1) s = s.substr(0, s.size()-3);
      |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~

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