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

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

输入排序过的链表，删除相同的元素。

挺简单的题目，头脑有点乱，搞的了做了半小时才做出来。。

/**
 * 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) //空结点或者单节点直接返回
            return head;
        ListNode t = head;
        while(true){
            if(t==null||t.next==null) //到链表尾或者下一个是链表尾
                break;  
            while(t.next!=null&&t.next.val==t.val) //迭代排除相同的，注意考虑到了链表尾
                t.next=t.next.next;
            t= t.next;
        }
        return head;
    }
}

LeetCode Remove Duplicates from Sorted List