LeetCode题解——Remove Linked List Elements

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

Credits:

Special thanks to @mithmatt for adding this problem and creating all test cases.

* struct ListNode {
*     int val;
*     ListNode *next;
*     ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* removeElements(ListNode* head, int val) {
ListNode* newhd =  new ListNode(0);
newhd->next = head;
ListNode* newlist = newhd;
while(newhd!=NULL && newhd->next!=NULL){
if(newhd->next->val == val)
{
newhd->next = newhd->next->next;
}
else newhd = newhd->next;
}
return newlist->next;
}
};

注意，若代码中ListNode* newlist = newhd->next;

最后return newlist,则结果将出现错误