void remove() { sl.size--; if (sl.first == this) sl.first = next; else prev.next = next; if (sl.last == this) sl.last = prev; else next.prev = prev; }
StateListNode(State q, StateList sl) { this.q = q; this.sl = sl; if (sl.size++ == 0) sl.first = sl.last = this; else { sl.last.next = this; prev = sl.last; sl.last = this; } }