Describe the concept and implementation of Dijkstra’s algorithm for finding the shortest path in a weighted graph.

1 Answers
Answered by suresh

Dijkstra's Algorithm for Finding the Shortest Path in Weighted Graphs

Dijkstra's algorithm is a popular method used to find the shortest path between nodes in a weighted graph. It is particularly useful in scenarios where distances between nodes are assigned weights, such as in road networks or computer networks.

Concept of Dijkstra's Algorithm

The main idea behind Dijkstra's algorithm is to maintain a set of visited nodes and calculate the shortest distance to each node from a starting point. The algorithm iterates through all the nodes in the graph, updating the shortest distance to each node as it progresses.

At each step, the algorithm selects the node with the shortest distance from the starting point that has not been visited yet. It then calculates the distances to all the neighboring nodes from the selected node and updates the shortest distance if a shorter path is found. This process continues until the algorithm has visited all nodes or reached the target node.

Implementation of Dijkstra's Algorithm

The implementation of Dijkstra's algorithm typically involves using a priority queue to keep track of the nodes with the shortest distance. This allows for efficient selection of the next node to visit based on the current shortest distances.

Here is a simple pseudocode implementation of Dijkstra's algorithm:

function Dijkstra(graph, start):
    initialize distances to all nodes as infinity
    create a priority queue and insert start node with distance 0
    while priority queue is not empty:
        current node = node with shortest distance from priority queue
        for each neighbor of current node:
            calculate new distance to neighbor through current node
            if new distance is shorter than current distance:
                update neighbor's distance
                insert neighbor into priority queue

By following the steps of Dijkstra's algorithm and updating the shortest distances to each node, you can find the shortest path from the starting point to any node in a weighted graph.

Answer for Question: Describe the concept and implementation of Dijkstra’s algorithm for finding the shortest path in a weighted graph.