protected void insertKid(Node<K, V> old, K key, Node<K, V> left, Node<K, V> right) {
int ind = kids.indexOf(old);
if (ind < 0) {
// when the root splits, the two new nodes are added to the dummy
// new root
kids.add(left);
kids.add(right);
guides.add(key);
return;
}
kids.set(ind, left);
kids.add(ind + 1, right);
guides.add(ind, key);
if (isOverFull()) {
split();
}
}
