23 lines
308 B
Go
23 lines
308 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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func main() {
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}
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func detectCycle(head *ListNode) *ListNode {
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hash := make(map[*ListNode]struct{})
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for head != nil {
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if _, ok := hash[head.Next]; ok {
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return head.Next
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}
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hash[head] = struct{}{}
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head = head.Next
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}
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return nil
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}
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