Algorithms For Dummies

  Reconnecting the Dots 

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spanning tree. Another function, 

represent_tree

, turns the key and value pairs 

of the dictionary into a tuple and then sorts each of the resulting tuples for better 

readability of the tree path:

def represent_tree(treepath):

    progression = list()

    for node in treepath:

        if node != treepath[node]:

            progression.append((treepath[node], node))

    return sorted(progression, key=lambda x:x[0])

print (represent_tree(treepath))

[('A','B'), ('B','C'), ('B','D'), ('D','E'), ('E','F')]

The 

represent_tree

 function reorders the output of Prim’s algorithm for better 

readability. However, the algorithm works on an undirected graph, which means 

that you can traverse the edges in both directions. The algorithm incorporates this 

assumption because there is no edge directionality check to add to the priority 

queue for later processing.