foo.cc: In function 'void trans(int)':
foo.cc:23:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |         for(int i=0;i<ans.size();i++)
      |                     ~^~~~~~~~~~~
foo.cc:28:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |                         if(i==(ans.size()-1)) ans.push_back(1);
      |                            ~^~~~~~~~~~~~~~~~

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