112. Remove Duplicates from Sorted List

题目

https://www.lintcode.com/problem/remove-duplicates-from-sorted-list/description?_from=ladder&&fromId=2

实现

1. 遍历链表
2. 如果当前节点和下一个节点相等，那么就当前节点的 next 指向下下一个节点
3. 如果当前节点和下一个节点不相等，那么更新 node = node.next

代码

class ListNode(object):
    def __init__(self, val, next=None):
        self.val = val
        self.next = next


class Solution:
    """
    @param head: head is the head of the linked list
    @return: head of linked list
    """

    def deleteDuplicates(self, head):
        if head is None:
            return head

        node = head

        while node.next is not None:
            # 如果相等就指向下一个节点，相当于尝试看下下个节点是否还相等
            if node.val == node.next.val:
                node.next = node.next.next
            # 如果不相等就更新 node
            else:
                node = node.next

        return head