Compilare: user.cpp: In function ‘void do_test(std::ifstream&, std::ofstream&)’: user.cpp:71:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poly1.size() <= x){ ^ user.cpp:78:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poly2.size() <= x){ ^ user.cpp:84:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < rez.size(); ++i){ ^ user.cpp: In instantiation of ‘void fft(T, int) [with int arg_mult = 1; T = __gnu_cxx::__normal_iterator<std::complex<double>*, std::vector<std::complex<double> > >]’: user.cpp:52:24: required from here user.cpp:37:12: warning: unused variable ‘n2’ [-Wunused-variable] const int n2 = n/2; ^ user.cpp: In instantiation of ‘void fft(T, int) [with int arg_mult = -1; T = __gnu_cxx::__normal_iterator<std::complex<double>*, std::vector<std::complex<double> > >]’: user.cpp:58:24: required from here user.cpp:37:12: warning: unused variable ‘n2’ [-Wunused-variable]