_ar2s_helpm()
{
   comp1=or();
   comp2=and();
   incount=0;
   gen=comp1.out;
   pro=comp2.out;
}

_ar2s_helpm.input(v_gen,v_pro);
{
   comp2.input(v_pro);
   temp=and();
   list_pro[incount]=v_pro;
   for (i=0; i<incount; i++)
   {
      temp.input(list_pro[i]);
   }
   temp.input(v_gen);
   detach(temp);
   comp1.input(temp[incount].out);
   incount++;
}

adder_twostages_byradu(a,b,inflg,n)
{
   base=4;
   while (base*base<=n) base*=2;
   for (i=0; i<n; i++)
   {
      cy_gen[i]=and(a[i],b[i]).out;
      cy_pro[i]=or(a[i],b[i]).out;
   }
   bl=4;

   while (bl<=base) {
      for (i=0; i<n; i+=bl)
      {
         i_[bl][i]=_ar2s_helpm();
         for (j=bl-1; j>=0; j--)
         {
            i_[bl][i].input(cy_gen[i+j],cy_pro[i+j]);
         }
         if (bl<>base) i+=bl;
      }
      bl*=2;
   }
   andall=and();
   flags.zero=andall.out;
   flags.cy=carry[n].gen;
   flags.ov=xor(carry[n].gen , carry[n-1].gen).out;
   for (i=0; i<=n; i++)
   {
      out[i]=xor(carry[i].gen,a[i],b[i]).out;
      andall.input(out[i]);
      carry[i]=_ar2s_helpm();

      j=i;
      while (j%4>0)
      {
         carry[i].input(cy_gen[i],cy_pro[i]);
         j-=1;
      }
      bl=4;
      while (bl<base)
      {
         if (j%bl>0)
         {
            j-=bl;
            carry[i].input(i_[bl][j].gen,i_[bl][j].out);
         }
         bl*=2;
      }
      while (j>0)
      {
         j-=base;
         carry[i].input(i_[base].[j].gen,i_[base].[j].pro);
      }
      carry[i].input(inflg.cy,0);
   }
}