LeetCode 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.

思路：比较简单。

/**
 * 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) {
    	ListNode root = head;
    	while (head != null) {
    		while (head.next != null && head.val == head.next.val)
    			head.next = head.next.next;
    		head = head.next;
    	}
    	return root;
    }
}