BFS Time Complexity (Big-O)

Breadth-first search runs in O(V + E) time and O(V) space, exploring a graph layer by layer from a source vertex. It is the canonical algorithm for shortest paths in an unweighted graph.

Key facts

Frequently asked questions

What is the time complexity of BFS?

O(V + E), where V is vertices and E is edges.

What is BFS used for?

Shortest path in an unweighted graph and level-order traversal.

Related pages

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