leetcode 83 删除排序链表中的重复元素
z
 2019-07-06 18:57:46  

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:

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2
输入: 1->1->2
输出: 1->2

示例 2:

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2
输入: 1->1->2->3->3
输出: 1->2->3
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# 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:
            return head
        pre = head
        p = head.next
        while p:
            while p and p.val == pre.val:
                p = p.next
            if not p:
                break
            else:
                pre = pre.next
                pre.val = p.val
                p = p.next
        pre.next = None
        return head