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Question 6 [30 marks] 4.2.7 The indegree of a vertex in a digraph is the number of directed edges that point to that vertex. The outdegree of a vertex in a digraph is the number of directed edges that emanate from that vertex. No vertex is reachable from a vertex of outdegree 0, which is called a sink; a vertex of indegree 0, which is called a source, is not reachable from any other vertex. A digraph where self-loops are allowed and every vertex has outdegree 1 is called a map (a function from the set of integers from 0 to V-1 onto itself). write pseudo code for