Forbidden Cities

There are n cities and m roads between them. Kaaleppi is currently in city a and wants to travel to city b. However, there is a problem: Kaaleppi has recently robbed a bank in city c and can't enter the city, because the local police would catch him. Your task is to find out if there is a route from city a to city b that does not visit city c. As an additional challenge, you have to process q qu