Dijkstra Algorithm Questions Long
The predecessor array in the Dijkstra Algorithm is used to keep track of the shortest path from the source vertex to each vertex in the graph. It stores the immediate predecessor of each vertex in the shortest path tree.
The main role of the predecessor array is to help reconstruct the shortest path from the source vertex to any other vertex in the graph. By following the predecessor array from the destination vertex back to the source vertex, we can determine the sequence of vertices that form the shortest path.
During the execution of the Dijkstra Algorithm, as the shortest path to each vertex is discovered, the predecessor array is updated accordingly. When a shorter path to a vertex is found, the predecessor of that vertex is updated to the vertex from which the shorter path is discovered.
By using the predecessor array, we can easily trace back the path from any vertex to the source vertex. This is particularly useful when we need to find the shortest path between two specific vertices in a graph.
In summary, the predecessor array plays a crucial role in the Dijkstra Algorithm by storing the immediate predecessor of each vertex in the shortest path tree, allowing us to reconstruct the shortest path from the source vertex to any other vertex in the graph.