Compilare: user.cpp: In function ‘std::vector<std::complex<_Tp> > intersect_poly_halfplane(const std::vector<std::complex<_Tp> >&, const std::complex<_Tp>&, const std::complex<_Tp>&)’: user.cpp:401:6: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (N == 1) if (! clockwise(A,B,V[0]) ) return V; else return res; ^ user.cpp: In function ‘int main()’: user.cpp:113:46: warning: unused variable ‘_NN’ [-Wunused-variable] #define re(II, NN) for (int II(0), _NN(NN); (II) < (NN); ++(II)) ^ user.cpp:566:3: note: in expansion of macro ‘re’ re (i, N) { ^ user.cpp:113:46: warning: unused variable ‘_NN’ [-Wunused-variable] #define re(II, NN) for (int II(0), _NN(NN); (II) < (NN); ++(II)) ^ user.cpp:606:3: note: in expansion of macro ‘re’ re (i, N) { ^