}
private void gather(TaskList tl, HashSet<Tree<T>>[] ht, HashSet<Tree<T>> target, Tree[] trees, int i) {
if (i==ht.length) {
}
private void gather(TaskList tl, HashSet<Tree<T>>[] ht, HashSet<Tree<T>> target, Tree[] trees, int i) {
if (i==ht.length) {