Given a linked list, remove the nth node from the end of list and return its head. For example,
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.
Note:
Given n will always be valid.
Try to do this in one pass.
删除链表的倒数第n个元素。n保证合法。要求走一趟搞定。
代码来自这位大神
简直牛X!
ListNode *removeNthFromEnd(ListNode *head, int n)
{
ListNode dummy(-1);
dummy.next = head;
ListNode *pre = &dummy;
while (--n > 0) head = head->next;
while (head->next)
{
pre = pre->next;
head = head->next;
}
pre->next = pre->next->next;
return dummy.next;
}