LeetCode 203. Remove Linked List Elements

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Words count in article: 126 | Reading time ≈ 1

题目

Remove all elements from a linked list of integers that have value val.

Example:

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Input:  1->2->6->3->4->5->6, val = 6
Output: 1->2->3->4->5

思路

Easy.

代码

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# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution(object):
    def removeElements(self, head, val):
        """
        :type head: ListNode
        :type val: int
        :rtype: ListNode
        """
        while head and head.val == val:
            head = head.next
        if not head:
            return head
        prev, cur = head, head.next
        while cur:
            while cur and cur.val == val:
                cur = cur.next
            prev.next = cur
            if cur:
                prev, cur = prev.next, cur.next
        return head