LeetCode 83. Remove Duplicates from Sorted List

Question

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.

https://leetcode.com/problems/remove-duplicates-from-sorted-list/

• Solution1

class Solution {
    public ListNode deleteDuplicates(ListNode head) {
        ListNode cur = head;
        while (cur != null){
            while(cur.next != null && cur.val == cur.next.val)
                cur.next = cur.next.next;
            cur = cur.next;
        }
        return head;
    }
}

Complexity:

Time complexity: O(n)

Space complexity: O(1)