11.5.3 Step 3: Update Balance Factors

Updating balance factors works exactly the same way as in unthreaded AVL deletion (see Deleting an AVL Node Step 3 - Update).

440. <Steps 3 and 4: Update balance factors and rebalance after RTAVL deletion 440> =
assert (k > 0);
while (--k > 0) 
  {
    struct rtavl_node *y = pa[k];

    if (da[k] == 0) 
      {
        y->rtavl_balance++;
        if (y->rtavl_balance == +1)
          break;
        else if (y->rtavl_balance == +2) 
          {
            <Step 4: Rebalance after RTAVL deletion in left subtree 441>
          }
      } 
    else 
      {
        y->rtavl_balance--;
        if (y->rtavl_balance == -1)
          break;
        else if (y->rtavl_balance == -2) 
          {
            <Step 4: Rebalance after RTAVL deletion in right subtree 442>
          }
      }
  }

This code is included in 431.