Explain a DFS Function | Dataford Interview Questions

Without writing code, read a given DFS graph function and explain what it does, its time/space complexity, write test cases, and rename it appropriately.

Asked in the technical phone stage. Warmup on CodeSignal; reading only.

Review this function:

def process_graph(graph, start):
    visited = set()
    order = []

    def visit(node):
        if node in visited:
            return
        visited.add(node)
        order.append(node)
        for neighbor in graph.get(node, []):
            visit(neighbor)

    visit(start)
    return order

Assume graph is a dictionary from node labels to neighbor lists. State the traversal order for representative inputs, identify edge cases, provide at least five tests, and propose a descriptive replacement name.

Constraints

The graph is represented as a dictionary whose keys and node labels are strings.
Each adjacency list contains zero or more string node labels.
The graph may contain cycles, self-loops, duplicate edges, or disconnected components.
Traversal begins at the specified start node and visits only nodes reachable from it.
The expected order follows the given order of each adjacency list.

Function Signature

def depth_first_traversal(graph, start):

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