What is the purpose of the visited set in Dijkstra?

Question

On the Wikipedia page for Dijkstra\'s algorithm, they mark visited nodes so they wouldn\'t be added to the queue again. However, if a node is visited then there can be no dista

Answer 1

Yes, you're right. There's no need for the visited vector.

If a node is visited then there cannot exist a distance to that node that is shorter, so, as you said, checking alt < dist[v] is enough.

Take a look here: