Remove Duplicates from Sorted List, Leetcode 解题笔记

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.

很简单的一题,two pointer解决。

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    public ListNode deleteDuplicates(ListNode head) {
        if(head == null || head.next == null) return head;
        ListNode fast = head.next;
        ListNode slow = head;
        while(fast != null){
            if(fast.val != slow.val){
                fast = fast.next;
                slow = slow.next;
            }
            else{
                slow.next = fast.next;
                fast = fast.next;
            }
        }
        return head;
    }
}
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