[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.

class Solution {
public:
    ListNode *deleteDuplicates(ListNode *head) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int count=0;
        ListNode *p,*q;
        if(!head)return NULL;
        p=head;
        while(p->next){
            if(p->val==p->next->val){
                count++;
                if(count>1){
                    q=p->next;
                    p->next=p->next->next;
                    delete q;
                }
            }else{
                count=0;
                p=p->next;
            }
        }
        return head;
    }
};