double data_real[1024], data_imag[1024];
double coef_real[1024];
double coef_imag[1024];
int main()
{
  int i, j, k;
  double temp_real;
  double temp_imag;
  double Wr;
  double Wi;
  for (i=0; i<1024; i++)
    {
      data_real[i]=0.33*i;
      data_imag[i]=1;
      coef_real[i]=1;
      coef_imag[i]=1;
    }
  int groupsPerStage=1;
  int buttersPerGroup=1024/2;
  for (i=0; i<10; ++i)
    {
      for (j=0; j<groupsPerStage; ++j)
        {
          Wr=coef_real[(1<<i)-1+j];
          Wi=coef_imag[(1<<i)-1+j];
          for (k=0; k<buttersPerGroup; ++k)
            {
              temp_real=Wr*data_real[2*j*buttersPerGroup+buttersPerGroup+k]-Wi*data_imag[2*j*buttersPerGroup+buttersPerGroup+k];
              temp_imag=Wi*data_real[2*j*buttersPerGroup+buttersPerGroup+k]+Wr*data_imag[2*j*buttersPerGroup+buttersPerGroup+k];
              data_real[2*j*buttersPerGroup+buttersPerGroup+k]=data_real[2*j*buttersPerGroup+k]-temp_real;
              data_real[2*j*buttersPerGroup+k]+=temp_real;
              data_imag[2*j*buttersPerGroup+buttersPerGroup+k]=data_imag[2*j*buttersPerGroup+k]-temp_imag;
              data_imag[2*j*buttersPerGroup+k]+=temp_imag;
            }
        }
      groupsPerStage<<=1;
      buttersPerGroup>>=1;
    }
  double sum=0.0;
  for (i=0; i<1023; i++)
    sum+=11.1*data_real[i];
  return sum;
}
/* [Main] Success. */