题解 | #删除链表中重复的结点(优化)#

/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) :
        val(x), next(NULL) {
    }
};
*/
class Solution {
public:
    ListNode* deleteDuplication(ListNode* pHead) {
        if(pHead == NULL){
            return NULL;
        }
        if(pHead->next == NULL){
            return pHead;
        }
        ListNode* newhead = new ListNode(0);
        newhead->next = pHead;
        ListNode* temp = newhead;
        ListNode* front = pHead;
        ListNode* back = pHead->next;
       
     
        while(back !=NULL){
            if(front->val == back->val){
                while(front->val == back->val&& back!=NULL){
                    back = back->next;
               
                }
                temp->next = back;
              
                front = back;
                if(back!= NULL){
                    back = back->next;
                }
           
            }
            else{
                temp = temp->next;
                front = front->next;
                back = back->next;
            
            }
        }
           
        return newhead->next;

    }
};