There is an alternative way of implementing Dijkstras algorithm that avoids use of the locator pattern but increases the space used for the priority queue, Q, from O(n) to O(m) for a weighted graph, G, with n vertices and m edges. The main

idea of this approach is simply to insert a new key-value pair, (D[v], v), each time

the D[v] value for a vertex, v, changes, without ever removing the old key-value pair for v. This approach still works, even with multiple copies of each vertex being stored in Q, since the first copy of a vertex that is removed from Q is the copy with the smallest key. Describe the other changes that would be needed to the description of Dijsktras algorithm for this approach to work. Also, what is the running time of Dijkstras algorithm in this approach if we implement the priority queue, Q, with a heap?