【剑指Offer】（链表）删除链表中重复的结点

蔚落 2022-03-17 14:28 188阅读 0赞

**题目链接**：[https://www.nowcoder.com/practice/fc533c45b73a41b0b44ccba763f866ef?tpId=13&tqId=11209&tPage=3&rp=3&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking][https_www.nowcoder.com_practice_fc533c45b73a41b0b44ccba763f866ef_tpId_13_tqId_11209_tPage_3_rp_3_ru_ta_coding-interviews_qru_ta_coding-interviews_question-ranking]

#### 题目描述 ####

在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。 例如，链表1->2->3->3->4->4->5 处理后为 1->2->5

#### 解决方法 ####

/* struct ListNode { int val; struct ListNode *next; ListNode(int x) : val(x), next(NULL) { } }; */
    class Solution { 
    public:
        ListNode* deleteDuplication(ListNode* pHead)
        { 
            if(!pHead || !pHead->next) return pHead;
           
            ListNode *res=new ListNode(-1); //这里写成ListNode *res=nullptr会报错！！！
            res->next=pHead;
            ListNode *begin=res;
            while(begin->next){ 
                ListNode *end=begin->next;
                bool flag=false;
                while(end->next && begin->next->val==end->next->val) { end=end->next;flag=true;}
                if(flag) begin->next=end->next;
                else begin=begin->next;
                
            }
            return res->next;
        }
    };

[https_www.nowcoder.com_practice_fc533c45b73a41b0b44ccba763f866ef_tpId_13_tqId_11209_tPage_3_rp_3_ru_ta_coding-interviews_qru_ta_coding-interviews_question-ranking]: https://www.nowcoder.com/practice/fc533c45b73a41b0b44ccba763f866ef?tpId=13&tqId=11209&tPage=3&rp=3&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking