LeetCode 203. Remove Linked List Elements

问题描述：

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
AC代码：
ListNode* removeElements(ListNode* head, int val)
{
while(head->val == val)//确定头结点位置
head = head->next;
ListNode *p ,*q;
p = head;
q = head->next;
while(q)
{
if(q->val == val)
{
p->next = q->next;
q = q->next;
}
else
{
p = q;
q = q->next;
}
}
return head;
}