Dijkstras algorithm is an algorithm for finding the shortest paths between nodes in a weighted graph, which may represent, for example, road networks. It was conceived by computer scientist Edsger W. Dijkstra in 1956 and published three years later. The algorithm exists in many variants, but a more common variant fixes a single node as the "source" node and finds shortest paths from the source to all other nodes in the graph, producing a shortest-path tree. The algorithm uses a data structure for storing and querying partial solutions sorted by distance from the start. Dijkstras algorithm keeps track of the currently known shortest distance from each node to the source node and updates these values if it finds a shorter path. The algorithm can be used in GPS devices to find the shortest path between the current location and the destination, and it has broad applications in industry, especially in domains that require modeling networks. The basic steps of how Dijkstras algorithm works are:
- Start at the source node and analyze the graph to find the optimal shortest distance between the given node and all other nodes in the graph.
- Keep track of the currently known shortest distance from each node to the source node and update these values if it finds a shorter path.
- Once the algorithm finds the shortest path between the source node and destination node, mark the specific node as visited.
The time complexity of Dijkstras algorithm is O(V^2), where V is the number of nodes in the graph.