a. (7 marks) The pseudo-code for breadth-first search of a given graph, modified slightly from Drozdek,1 is as follows: void breadthFirstSearch (vertex w) for all vertices u num (u) = 0; edges - null; num(w) -i++ enqueue(w); while queue is not empty v = dequeue(); for all vertices u adjacent to v if num(u) is 0 num(u) - i++; enqueue (u); attach edge(vu) to edges; output edges; i (5 marks) Now consider the following directed graph. Give the breadth-first traversal of the graph, starting from vertex S. At any vertex where there is a choice of edge you should choose the next vertex to be visited based on alphabetic order