Question 1

What data structures are used to implement DFS and BFS?

Accepted Answer

DFS is typically implemented using a Stack (or recursion, which uses the call stack). BFS is implemented using a Queue. These data structures determine the order in which nodes are visited.

Question 2

When would you use DFS over BFS?

Accepted Answer

DFS is preferred when you need to explore a path to its full depth, such as in solving mazes or finding a path between two nodes. It is also more memory-efficient than BFS if the tree or graph is very wide. BFS is better for finding the shortest path between two nodes in an unweighted graph.

DFS vs. BFS Interview Questions

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