No person shall park a vehicle in any parking space during any period of time parking is permitted:
(a) When such space is occupied by another vehicle;
(b) So that any part of such vehicle occupies more than one such space or protrudes beyond any markings which may designate such space except that, at any place where parallel parking is permitted, a vehicle which is of a size too large to be parked within such space shall be permitted to occupy two adjoining parking spaces.