foo.cc: In function 'int main()':
foo.cc:50:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |  for(int i=0;i<ans.size();i++) cout<<ans[i]<<" ";
      |              ~^~~~~~~~~~~

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