题解 | #删除链表中重复的结点#

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
#
# @param pHead ListNode类
# @return ListNode类
#
class Solution:
    def deleteDuplication(self, pHead: ListNode) -> ListNode:
        # write code here
		
		'''
		遍历俩遍，将链表的值出现的次数存入哈希表，第二遍出现次数不等于1就删除
		'''
        cur = pHead
        Mydict = {}
        while cur:
            if cur.val not in Mydict.keys():
                Mydict[cur.val] = 1
                cur=cur.next
            else:
                Mydict[cur.val] += 1
                cur = cur.next

        newHead = ListNode(-1)
        newHead.next = pHead

        cur = newHead
        while cur.next:
            if Mydict[cur.next.val] != 1:
                cur.next = cur.next.next
            else:
                cur=cur.next
        return newHead.next