foo.cc: In function 'std::string strcmp(std::string, std::string)':
foo.cc:4:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    4 |  for(int i=1;i<=str1.size();i++){
      |              ~^~~~~~~~~~~~~

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