[203]Remove Linked List Elements

【题目描述】

Remove all elements from a linked list of integers that have value val.

Example
Given: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6
Return: 1 --> 2 --> 3 --> 4 --> 5

【思路】

无

【代码】

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode* removeElements(ListNode* head, int val) {
        ListNode* p,*q;
        p=q=head;
        while(p!=NULL){
           if(p->val==val){
               if(p==head){
                   head=p->next;
                   p=p->next;
               }
               else{
                   q->next=p->next;
                   p=p->next;
               }
           }
           else{
             q=p;
             p=p->next;   
           }
          
        }
        return head;
    }
};