Learn Algorithm Design by Building a Shortest Path Algorithm - Step 49

Tell us what’s happening:

I thought this was the right answer, any chance i could get a hint at what I did wrong?

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)]

def shortest_path(graph, start, target = ''):
    unvisited = list(graph)
    distances = {node: 0 if node == start else float('inf') for node in graph}
    paths = {node: [] for node in graph}
    while unvisited:
        current = min(unvisited, key=distances.get)
        for node, distance in graph[current]:
            if distance + distances[current] < distances[node]:
                distances[node] = distance + distances[current]
                if paths[node] and paths[node][-1] == node:
                    paths[node] = paths[current][:]

/* User Editable Region */

    targets_to_print = paths[target] if target != '' else graph

shortest_path(my_graph, 'A')

/* User Editable Region */

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Challenge Information:

Learn Algorithm Design by Building a Shortest Path Algorithm - Step 49

remove paths and !='' from the syntax

val_1 if condition else val_2
this is the correct syntax.

suppose there’s a variable a. a gets assigned val_1 if condition is true. here lets replace condition with a variable b. if b means if b has a value not 0 value (0 means false) then it becomes true.

I got that solved. Anyone who might get confused by val_1, you can re-read the instruction and take it to be literal.

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