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Remove Duplicates from Sorted List

Problem Statement​

Given the head of a sorted linked list, delete all duplicates such that each element appears only once. Return the linked list sorted as well.

Leetcode link

Example 1:​

Input: head = [1,1,2]
Output: [1,2]

Example 2:​

Input: head = [1,1,2,3,3]
Output: [1,2,3]

Constraints:​

  • The number of nodes in the list is in the range [0, 300].
  • -100 <= Node.val <= 100
  • The list is guaranteed to be sorted in ascending order.

Code​

Python Code
class Solution(object):
    def deleteDuplicates(self, head):
        """
        :type head: ListNode
        :rtype: ListNode
        """
        current = head
        while current and current.next:
            if current.val == current.next.val:
                current.next = current.next.next
            else:
                current = current.next
        return head