Linked List Cycle II LeetCode solution in Java

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public class Solution {
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  public ListNode detectCycle(ListNode head) {
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    if (head == null) return null;
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    ListNode tortoise = head;
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    ListNode hare = new ListNode();
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    hare.next = head.next;
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    while (hare != null && hare.next != null && hare != tortoise) {
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      tortoise = tortoise.next;
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      hare = hare.next.next;
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    }
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    if (hare == null || hare.next == null) return null;
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    tortoise = head;
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    while (tortoise != hare) {
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      tortoise = tortoise.next;
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      hare = hare.next;
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    }
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    return hare;
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  }
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}