Compilare: user.cpp: In function ‘std::vector<Complex> multiply(std::vector<Complex>, std::vector<Complex>)’: user.cpp:84:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(A.size() < dim) ~~~~~~~~~^~~~~ user.cpp:86:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(B.size() < dim) ~~~~~~~~~^~~~~ user.cpp:90:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < A.size(); i++) ~~^~~~~~~~~~ user.cpp:93:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < C.size(); i++) ~~^~~~~~~~~~ user.cpp: In function ‘void Solve()’: user.cpp:131:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = X.size() - 1; i < Y.size(); i++) ~~^~~~~~~~~~