Dijkstra Algorithm Questions Medium
The role of a priority queue in the Dijkstra Algorithm is to efficiently select the next vertex to visit during the graph traversal process. The algorithm maintains a priority queue of vertices, where the priority of each vertex is determined by its current distance from the source vertex.
Initially, all vertices are assigned a distance of infinity except for the source vertex, which is assigned a distance of 0. As the algorithm progresses, it continuously updates the distances of the vertices based on the edges' weights.
The priority queue ensures that the vertex with the smallest distance is always selected next. This allows the algorithm to prioritize visiting the vertices that are closest to the source vertex, gradually expanding the search outward.
By selecting the vertex with the smallest distance from the priority queue, the Dijkstra Algorithm guarantees that it explores the shortest path to each vertex in a greedy manner. This process continues until all vertices have been visited or until the destination vertex is reached, resulting in the shortest path from the source vertex to all other vertices in the graph.