/* public class ListNode { public int val; public ListNode next; public ListNode (int x) { val = x; } }*/ class Solution { public ListNode EntryNodeOfLoop(ListNode pHead) { // write code here ListNode slow = pHead; ListNode fast = pHead; while(fast != null && fast.next != null){ slow = slow.next; fast = fast.next.next; if(slow == fast){ ListNode np = pHead; while(np != slow){ np = np.next; slow = slow.next; } return np; } } return null; } }