Circular Array Loop

Explore how to detect cycles in circular arrays where each element directs forward or backward movement. Learn to apply the fast and slow pointers method to determine if a cycle of consistent direction exists, helping you solve related coding interview problems effectively.

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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 ...