[LC] 19. Remove Nth Node From End of List

Given a linked list, remove the n-th node from the end of list and return its head.

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.

Follow up:

Could you do this in one pass?

 # Definition for singly-linked list.
 # class ListNode(object):
 #     def __init__(self, x):
 #         self.val = x
 #         self.next = None

 class Solution(object):
     def removeNthFromEnd(self, head, n):
         """
         :type head: ListNode
         :type n: int
         :rtype: ListNode
         """
         dummy = ListNode(-1)
         dummy.next = head
         cur, slow = dummy, dummy
         while n > 0:
             cur = cur.next
             n -= 1
         while cur.next is not None:
             slow = slow.next
             cur = cur.next
         slow.next = slow.next.next
         return dummy.next