typedef struct
{
  double re, im;
} complexe;

complexe complexe_init(double, double);
double   complexe_re(complexe);
double   complexe_im(complexe);
complexe complexe_somme(complexe, complexe);
complexe complexe_difference(complexe, complexe);
complexe complexe_produit(complexe, complexe);
double   complexe_module(complexe);
double   complexe_distance(complexe, complexe);