Detect a Cycle (Floyd's Cycle Finding)

Updated Apr 28, 2026

Short answer

Using two pointers (slow and fast) moving at different speeds to see if they meet.

Deep explanation

Intermediate linked list questions test pointer manipulation logic. Using two pointers (slow and fast) moving at different speeds to see if they meet.

Real-world example

Back/Forward navigation in web browsers.

Common mistakes

  • Losing the reference to the rest of the list during pointer re-assignment.

Follow-up questions

  • Time Complexity?

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