foo.cc: In function 'int main()':
foo.cc:13:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |  for(int i=0;i<now.length();i++)
      |              ~^~~~~~~~~~~~~
foo.cc:17:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |  for(int i=0;i<now.length()-2;i++)
      |              ~^~~~~~~~~~~~~~~
foo.cc:22:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |   for(int j=0;j<now.length()-2;j++)
      |               ~^~~~~~~~~~~~~~~
foo.cc:39:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::set<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |  for(int i=0;i<list2.size();i++)
      |              ~^~~~~~~~~~~~~

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