Floyd's algorithm is the standard for cycle detection with space. When you see linked lists with possible cycles, think tortoise and hare. It is fast and effective. The two-phase approach generalizes. Detect first, then locate. This pattern appears in many functional graph problems.
Separation of concerns makes debugging easier. Always handle the no-cycle case by checking for null pointers before dereferencing. Forgetting this check is a common bug that crashes your program.