力扣—Remove Duplicates from Sorted List（删除排序链表中的重复元素）python实现

题目描述：

中文：

给定一个排序链表，删除所有重复的元素，使得每个元素只出现一次。

示例 1:

输入: 1->1->2
输出: 1->2

示例 2:

输入: 1->1->2->3->3
输出: 1->2->3

英文：

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

Example 1:

Input: 1->1->2
Output: 1->2

Example 2:

Input: 1->1->2->3->3
Output: 1->2->3

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

class Solution(object):
    def deleteDuplicates(self, head):
        """
        :type head: ListNode
        :rtype: ListNode
        """
        if not head or not head.next:
            return head
        dummy=ListNode(0)
        dummy.next=head
        p=head
        while p.next:
            if p.next.val==p.val:
                p.next=p.next.next
            else:
                p=p.next
        return dummy.next

题目来源：力扣