LeetCode Remove Duplicates from Sorted List II

// 60ms
 1 /**
 * 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) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        ListNode temp(0);
        ListNode *q,*p;
 
        
        q=&temp;
        q->next=head;             
        p=head;
        
        while(p)
        { 
            if(p->next&&p->val==p->next->val)
            {  
                while(p->next&&p->val==p->next->val)
                {
                    p->next=p->next->next;
                    q->next=p->next;
                }               
            }
            else
            {
                q=p;
            }
            p=p->next;
        }
        return temp.next;
    }
};