82. Remove Duplicates from Sorted List II
Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
For example,
Given 1->2->3->3->4->4->5, return 1->2->5.
Given 1->1->1->2->3, return 2->3.
Solution:
class Solution(object):
def deleteDuplicates(self, head):
"""
:type head: ListNode
:rtype: ListNode
"""
pre = node = dummy = ListNode(None)
pre.next = head
cur = head
while cur:
if cur.val != pre.val and (not cur.next or cur.val != cur.next.val):
node.next = cur
node = cur
pre = cur
cur = cur.next
node.next = None
return dummy.next