foo.cc: In function 'int main()':
foo.cc:19:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |                 for (int j = 0; j < formula.size(); j++) {
      |                                 ~~^~~~~~~~~~~~~~~~
foo.cc:30:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for(int i=0;i<ans.size();i++){
      |                     ~^~~~~~~~~~~

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