Implement BFS to Find Shortest Path in Graph

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This is a Medium difficulty Coding & Algorithms question, commonly asked during Technical Screen rounds at Amazon.

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This question is commonly asked for Data Scientist candidates at Amazon during technical interviews.

Question

##### Scenario

Social network needs to compute the shortest friend-distance between two users in an undirected graph containing millions of nodes.

##### Question

Implement an iterative BFS that returns the minimum number of hops between a source and target user. Extend the function to also return one of the actual shortest paths.

##### Hints

Use a queue, visited set, and early exit when target is found.

PracHub · Accepted Answer

This question evaluates understanding of graph traversal algorithms, particularly breadth-first search, and competency in computing shortest paths and reconstructing an example shortest route in large undirected graphs.

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Implement BFS to Find Shortest Path in Graph