Woodstock Blog

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[LeetCode 83] Remove Duplicates From Sorted List



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

For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.


Frequency 3
Difficulty 1
Adjusted Difficulty 1
Time to use --------

Ratings/Color = 1(white) 2(lime) 3(yellow) 4/5(red)


This question is trivial. The next following up question is not easy.


my code

public ListNode deleteDuplicates(ListNode head) {
    if (head == null) return null;
    ListNode pre = head;
    ListNode post = head;
    while (post != null){
        post = post.next;
        if (post == null || pre.val != post.val){
            pre.next = post;
            pre = post;
    return head;