y->avl_link[1] = x->avl_link[0];
x->avl_link[0] = y;
pa[k - 1]->avl_link[da[k - 1]] = x;
if (x->avl_balance == 0)
  {
    x->avl_balance = -1;
    y->avl_balance = +1;
    break;
  }
else
  x->avl_balance = y->avl_balance = 0;