Detect Cycle in Sequence

A medium Python interview practice problem on DataDriven. Write and execute real python code with instant grading.

Domain

Python

Difficulty

medium

Seniority

junior

Problem

Our dependency resolver needs to detect infinite loops in task chains. Given a list of integers where each value points to the next index to visit (-1 means end), determine whether following the chain from index 0 revisits an index. Return True if a cycle exists.

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