[leetcode]83.Remove Duplicates from Sorted List

题目

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

Example 1:

Input: 1->1->2
Output: 1->2
Example 2:

Input: 1->1->2->3->3
Output: 1->2->3

解法

思路

其实刚看到这道题，我直接想到的是[leetcode]26.Remove Duplicates from Sorted Array这道题的思路，所以设置了一个快指针和一个慢指针。

代码

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