What is BFS and how is it used in coding interviews?

What is BFS and how is it used in coding interviews?

BFS, or Breadth-First Search, is an algorithm for traversing or searching tree or graph data structures. In coding interviews, it's often used to solve problems related to shortest paths, level order traversal, and more.

Can you give me an example of a BFS problem?

Sure! A common BFS problem is finding the shortest path in an unweighted graph. For instance, given a grid, you can use BFS to find the shortest path from the top-left corner to the bottom-right corner.

What are the time and space complexities of BFS?

The time complexity of BFS is O(V + E), where V is the number of vertices and E is the number of edges. The space complexity is O(V) due to the storage of the queue.

How does BFS differ from DFS?

BFS explores all neighbors at the present depth prior to moving on to nodes at the next depth level, while DFS explores as far as possible along a branch before backtracking.