remove-duplicates-from-sorted-list.py

'''
Given a sorted linked list, delete all duplicates such that each element appear only once.

Example 1:

Input: 1->1->2
Output: 1->2
Example 2:

Input: 1->1->2->3->3
Output: 1->2->3
''''


# 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
        """
        # 注意边界条件
        tmp = head
        while tmp and tmp.next:
            if tmp.val == tmp.next.val:
                tmp.next = tmp.next.next
            else:
                tmp = tmp.next
        return head