思想:
由于链表是排序的,只要判断head和head.next的val值是否相等,若相等则head.next = head.next.next 反之head = head.next
为了返回,将head暂存dummy
# Definition for singly-linked list.
# class ListNode:
# def __init__(self, x):
# self.val = x
# self.next = None
class Solution:
def deleteDuplicates(self, head):
"""
:type head: ListNode
:rtype: ListNode
"""
dummy= head
while head and head.next:
if head.val == head.next.val:
head.next = head.next.next
else:
head = head.next
return dummy