/in/foo.cc: In function 'void build_next()':
/in/foo.cc:26:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |         while(i < n.length())
      |               ~~^~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:50:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |         for(int i = 0, j = 0; i < s.length(); i++)
      |                               ~~^~~~~~~~~~~~
/in/foo.cc:57:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |                 if(j == n.length())
      |                    ~~^~~~~~~~~~~~~