Untitled
unknown
kotlin
2 years ago
628 B
1
Indexable
Never
/** * Example: * var li = ListNode(5) * var v = li.`val` * Definition for singly-linked list. * class ListNode(var `val`: Int) { * var next: ListNode? = null * } */ class Solution { fun hasCycle(head: ListNode?): Boolean { if (head == null) return false tailrec fun iterate(fast: ListNode?, lazy: ListNode?): Boolean = if (fast == null || lazy == null) false else if (fast == lazy) true else iterate(fast = fast.next?.next, lazy = lazy.next) return iterate(fast = head.next?.next, lazy = head) } }