sol.py

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

# Two Pass
class Solution:
    def removeNthFromEnd(self, head, n):
        """
        :type head: ListNode
        :type n: int
        :rtype: ListNode
        """
        curr = head
        count = 0
        while curr is not None:
            count+=1
            curr = curr.next
        bad_node = count-n+1
        curr = head
        ll = ListNode(None)
        trav = ll
        for enum in range(bad_node-1):
            trav.next = ListNode(curr.val)
            trav = trav.next
            curr = curr.next
        curr = curr.next
        while curr is not None:
            trav.next = ListNode(curr.val)
            trav = trav.next
            curr = curr.next
        return ll.next