Design a three-bit counter-like circuit controlled by the input w. If w=0, then the counter subtracts 1 from its contents (acting like a normal down-counter). If w=1, then the counter adds 2 to its contents, wrapping around if the count has to become 8 or 9. Thus if the current state is 6 (or 7) and w=1, then the next state is 0 (or 1). Use D flip-flops in the circuit.