@Override
TrieNode add(final TrieLeaf o, final int l, final InputInfo ii) throws QueryException {
final int k = key(o.hash, l);
final TrieNode ch = kids[k], nw;
if (ch != null) {
final TrieNode ins = ch.add(o, l + 1, ii);
if (ins == ch) return this;
nw = ins;
} else nw = o;
final TrieNode[] ks = copyKids();
ks[k] = nw;
// we don't replace here, so the size must increase
return new TrieBranch(ks, used | 1 << k, size + 1);
}
@Override
TrieNode addAll(final TrieNode o, final int l, final InputInfo ii) throws QueryException {
return o.add(this, l, ii);
}