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.
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* deleteDuplicates(ListNode* head) {
if(head== NULL || head->next == NULL) return head;
ListNode *p = head;
ListNode *q = NULL;
int a,b;
while(p->next)
{
q=p->next;
a=p->val;
b=q->val;
if(a==b)
{
ListNode *tmp=q;
q=q->next;
p->next = q;
free(tmp);
}
else
{
p = q;
q = q->next;
}
}
return head;
}
};
(leetcode)Remove Duplicates from Sorted List
原文：http://www.cnblogs.com/chdxiaoming/p/4567201.html