Shortest Path Algorithms (Dijkstra's Algorithm)

Question 1

What is Dijkstra’s Algorithm used for?

Answer 1

To find the shortest path from a source vertex to all other vertices in a graph with non-negative weights.

Question 2

How does Dijkstra’s Algorithm work?

Answer 2

Uses a priority queue to pick the node with the shortest tentative distance and updates its neighbors accordingly.

Question 3

What is the time complexity of Dijkstra’s Algorithm?

Answer 3

O((V + E) log V) using a min-priority queue.

Question 4

Can Dijkstra’s Algorithm handle negative weights?

Answer 4

No — it assumes that once a node’s shortest path is found, it won’t be improved.