Compilare: user.cpp: In function ‘std::vector<int> prod(std::vector<int>, std::vector<int>)’: user.cpp:37:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<A.size();i++) ^ user.cpp:39:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<B.size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:99:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<ans.size();i++) ^