Detect a cycle

Medium

Let's say you're given a singly linked list.

Write a function that determines if it has a cycle.

A cycle implies that the list has a loop, where a node points to a previous node in the list.

Here's an example of a singly linked list without a cycle, where Node 5 has no next node:

And here's a linked list with a cycle:

Note how Node 5 points back to Node 3.

Try it first

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None

def detect_cycle(head: Node) -> bool:
    # implement detect_cycle
    return False

1class Node:
2    def __init__(self, data):
3        self.data = data
4        self.next = None
5
6def detect_cycle(head: Node) -> bool:
7    # implement detect_cycle
8    return False
9

Solution

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