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Linked List Cycle

Given a list of values and an integer pos indicating where the tail connects to (0-indexed), determine if the linked list has a cycle.

pos is -1 if there is no cycle. Output True if there is a cycle, False otherwise.

Input:

3,2,0,-4
1

Output:

True

Reasoning:

The input list of values is used to create a linked list: 3 -> 2 -> 0 -> -4.
The integer pos is 1, meaning the tail of the list connects to the node at index 1 (0-indexed), which has a value of 2.
The connection creates a cycle: 3 -> 2 -> 0 -> -4 -> 2, since the last node (-4) points back to the node with value 2.
Because a cycle is detected in the linked list, the output is True.

Editor

Python 3.13.1

0/0

Run code to see test results.