Circular Array Loop

Explore how to identify cycles in circular arrays where elements dictate steps forward or backward. Understand the problem constraints and apply fast and slow pointer techniques to detect cycles, helping you prepare for coding interviews that test cycle detection patterns.

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Statement

There is a circular list of non-zero integers called nums. Each number in the list tells you how many steps to move forward or backward from your current position:

If nums[i] is positive, move nums[i] steps forward.
If nums[i] is negative, move nums[i] steps backward.

As the list is circular:

Moving forward from the last element takes you back to the first element.
Moving backward from the first element takes you to the last element.

A cycle in this list means:

You keep moving according to the numbers, and you end up repeating a sequence of ...