How do Depth-First Search and Breadth-First Search differ?

What are the main differences between Depth-First Search and Breadth-First Search?

Depth-First Search (DFS) explores as far as possible along each branch before backtracking, while Breadth-First Search (BFS) explores all neighbors at the present depth prior to moving on to nodes at the next depth level.

Can you give me an example of when to use DFS over BFS?

DFS is often used in scenarios where you want to explore all possibilities, like solving puzzles or mazes, while BFS is better for finding the shortest path in unweighted graphs.

What are the time and space complexities of both algorithms?

Both DFS and BFS have a time complexity of O(V + E), where V is the number of vertices and E is the number of edges. However, DFS can have a space complexity of O(h) where h is the maximum height of the tree, while BFS has a space complexity of O(V) due to the queue used.

Are there any specific use cases for BFS?

Yes, BFS is commonly used in scenarios like finding the shortest path in a maze, web crawling, and peer-to-peer networking.