LeetCode142-环形链表II
LeetCode142-环形链表II
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| public ListNode detectCycle(ListNode head) { ListNode fast = head, snow = head; while (fast != null && fast.next != null) { fast = fast.next.next; snow = snow.next; if (snow == fast) break; } if (fast == null || fast.next == null) { return null; } snow = head; while (snow != fast) { snow = snow.next; fast = fast.next; } return snow; }
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