00009

力扣 203 移除链表元素

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* removeElements(ListNode* head, int val) {
        ListNode* dummyHead = new ListNode(0);
        dummyHead -> next = head;
        ListNode* cur = dummyHead;
        while(cur -> next != NULL){
            if(cur->next->val == val ){
                ListNode* tmp = cur -> next;
                cur->next = cur->next->next;
                delete cur -> next;
            }
            else{
                cur = cur -> next;
            }
        }
        head = dummyHead -> next;
        delete dummyHead;
        return head;
    }
};