Learn Algorithm Design by Building a Shortest Path Algorithm - Step 34

Tell us what’s happening:

Hey coders.

The instructions: You should have a while loop that executes while unvisited is not empty. Don't forget the pass keyword. I believe that’s what I did?

Your code so far

my_graph = {
    'A': [('B', 3), ('D', 1)],
    'B': [('A', 3), ('C', 4)],
    'C': [('B', 4), ('D', 7)],
    'D': [('A', 1), ('C', 7)]
}


/* User Editable Region */

def shortest_path(graph, start):
    unvisited = list(graph)
    distances = {node: 0 if node == start else float('inf') for node in graph}
    paths = {node: [] for node in graph}
    paths[start].append(start)

    while unvisited != ' ': 
        pass

    print(f'Unvisited: {unvisited}\nDistances: {distances}\nPaths: {paths}')
    
#shortest_path(my_graph, 'A')

/* User Editable Region */

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Challenge Information:

Learn Algorithm Design by Building a Shortest Path Algorithm - Step 34

Ah, this one is a bit tricky. The step wants you to use “truthiness”. Basically, a list acts like True when it has element and like False when its empty.

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Oh okay! But what am I supposed to put in the quotes/brackets? I tried while unvisited = list(graph) (what it was originally equal to, but that still shows an error.

The variable unvisited itself is a condition - its inherently going to act like True or False depending upon if its empty.

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