Question Definition
Given a linked list, remove the nth node from the end of list and return its head. For example,
Given linked list: 1->2->3->4->5, and n = 2.
After removing the second node from the end, the linked list becomes 1->2->3->5.
Note:
Given n will always be valid. Try to do this in one pass.
Java Solution
public ListNode removeNthFromEnd(ListNode head, int n) {
ListNode fast = head;
while(fast != null && --n >= 0){
fast = fast.next;
}
if(n == 0 && fast == null)
return head.next;
if(fast == null) return head;
ListNode slow = head;
while(fast.next != null)
{
slow = slow.next;
fast = fast.next;
}
slow.next = slow.next.next;
return head;
}
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