Clone a Graph | Dataford Interview Questions

Clone a graph (coding problem).

Asked in the technical panel, manager plus 2 senior developers. This was a live-coding exercise.

Input and Output

Implement clone_graph(graph). The input is a dictionary mapping each string node label to a list of adjacent string labels. The graph may contain cycles, self-loops, isolated nodes, and disconnected components. Every referenced neighbor appears as a key in graph.

Return a new adjacency-list dictionary representing a deep copy of the graph. Preserve every node and edge, but create new adjacency lists rather than returning the input object.

Constraints

0 <= number of nodes <= 10^4
Each node label is a non-empty string
Each neighbor reference is valid
The graph may be directed
The graph may contain cycles, self-loops, and disconnected components

Function Signature

def clone_graph(graph):

Your question is Clone a Graph. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem