Leetcode - Remove Duplicates from Sorted List Solution

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.

Example 1:

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

Example 2:

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


  • 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.

Solution in python

# Definition for singly-linked list
class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

class Solution:
    def deleteDuplicates(self, head: ListNode) -> ListNode:
        curr_node = head
        while curr_node and curr_node.next:
            next_node = curr_node.next
            while next_node and curr_node.val == next_node.val:
                next_node = next_node.next
            curr_node.next = next_node
            curr_node = next_node
        return head

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