Remove Nth Node From End of List

Given linked list: 1->2->3->4->5, and n = 2.

After removing the second node from the end, the linked list becomes 1->2->3->5.

ListNode* removeNthFromEnd(ListNode* head, int n) {
if(head==NULL)
return NULL;
ListNode* pFront=head;
ListNode* p=head;
ListNode* q=head;
for(int i=0; i<(n-1); i++){
q=q->next;
}
while(q->next){
pPre = p;
p = p->next;
q = q->next;
}
if(pFront==NULL){
head=p->next;
delete p;
}
else{
pFront->next=p->next;
delete p;
}
return head;
}