foo.cc: In function 'void monomial(int)':
foo.cc:20:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for(int k=0;k<a.size();k++){
      |                     ~^~~~~~~~~
foo.cc:24:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |                         if(k<a.size()-1){
      |                            ~^~~~~~~~~~~
foo.cc:33:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |                         if(k<a.size()-1){
      |                            ~^~~~~~~~~~~

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