LeetCode203.移除链表元素

代码随想录链接

我的解法： 

/**
 * 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) {
        while(head != nullptr && head->val == val){
            head = head->next;
        }
        if(head==nullptr) return head;

        //第一个节点不等于val
        ListNode * left = head;
        ListNode * right = head->next;

        while(right != nullptr){
            if(right->val == val){       //删除节点
                left->next = right->next;
                right = right->next;
            }
            else{
                left = right;
                right = right->next;
            }
        }
        return head;
    }
};