Remove Duplicates from Sorted List - LeetCode

题目：

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.

分析：

这道题目应该就是考一个基本的链表删除，没什么难度，我用一个变量now记录现结点的val，若与下一个结点的val不一样，则把now替换成现结点的val；否则用

delete函数删除现结点，并且跳到下一个结点。

代码：

class Solution:    # @param head, a ListNode    # @return a ListNode    def deleteDuplicates(self, head):        now = 0        prev = head        temp = head        while head is not None:            if now != head.val:                now = head.val                prev = head                head = head.next            else:                head = self.delete(prev, head)        return temp        def delete(self,prev,head):        prev.next = head.next        del head        return prev.next