力扣的删除排序链表中的重复元素解法 （Python3）

力扣的删除排序链表中的重复元素解法

题目描述：
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
来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。

参考程序1：

"""
Definition of ListNode
class ListNode(object):
    def __init__(self, val, next=None):
        self.val = val
        self.next = next
"""
class Solution:
    """
    @param result: A ListNode
    @return: A ListNode
    """
    def deleteDuplicates(self, result):
        if result is None:
            return result
        record = set([result.val])
        cur, pre = result.next, result
        while cur:
            if cur.val in record:
                pre.next = cur.next
                cur = cur.next
            else:
                record.add(cur.val)
                pre = pre.next
                cur = cur.next
        return result

运行结果1：

参考程序2：

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    """
    @param result: A ListNode
    @return: A ListNode
    """
    def deleteDuplicates(self, result):
     R = result
     if result:
        while result and result.next:
            if result.val == result.next.val:
                result.next = result.next.next
            else:
                result = result.next
     return R

运行结果2：

参考程序3：

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    """
    @param result: A ListNode
    @return: A ListNode
    """
    def deleteDuplicates(self, result: ListNode) -> ListNode:
        if result is None:
            return result
        a = result
        b = result.next
        while b!=None:
            if b.val!=a.val:
                a = b
                b = b.next
            else:
                a.next = b.next
                b = b.next
        return result

运行结果3：

来源：CSDN

作者：chutu2018

链接：https://blog.csdn.net/chutu2018/article/details/104726990