foo.cc: In function 'int main(int, char**, char**)':
foo.cc:30:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for (int i = 0; i < s.size(); i++) {
      |                         ~~^~~~~~~~~~
foo.cc:62:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for (int i = 0; i < ans11.size(); i++) cout << ans11[i] << '\n';
      |                     ~~^~~~~~~~~~~~~~
foo.cc:65:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for (int i = 0; i < ans21.size(); i++) cout << ans21[i] << '\n';
      |                     ~~^~~~~~~~~~~~~~

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