foo.cc: In function 'int main()':
foo.cc:7:14: 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<n.size();i++)
      |             ~^~~~~~~~~
foo.cc:17:14: 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<n.size()-1;i++)
      |             ~^~~~~~~~~~~
foo.cc:24:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 | for(int i=0;i<n.size();i++)
      |             ~^~~~~~~~~

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