剑指offer 删除链表中重复的结点

题目

在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。 例如，链表1->2->3->3->4->4->5 处理后为 1->2->5

思路

遍历链表，跳过所有重复结点。

代码

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    def deleteDuplication(self, pHead):
        # write code here
        if not pHead or not pHead.next:
            return pHead
        node = pHead
        next = pHead.next
        pre = ListNode(0)
        pre.next = node
        res_pre = pre
        while node and next:
            if node.val == next.val:
                while next and node.val == next.val:
                    next = next.next
                pre.next = next
                node = next
                if node:
                    next = node.next
            else:
                pre = node
                node = node.next
                next = next.next
        return res_pre.next