29 lines
519 B
Go
29 lines
519 B
Go
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package main
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type ListNode struct {
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Val int
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Next *ListNode
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}
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// This solution uses O(1) memory, but
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// runtime duration is a bit more
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// unpredictable with a maximum complexity
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// of O(n^2) I think.
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/**
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* Definition for singly-linked list.
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* type ListNode struct {
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* Val int
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* Next *ListNode
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* }
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*/
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func hasCycle(head *ListNode) bool {
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slow, fast := head, head
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for fast != nil && fast.Next != nil {
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slow, fast = slow.Next, fast.Next.Next
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if slow == fast {
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return true
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}
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}
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return false
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}
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