00014

力扣 19 删除链表的倒数第N个节点

class Solution:
    def removeNthFromEnd(self, head: Optional[ListNode], n: int) -> Optional[ListNode]:
        dummy_head = ListNode(next = head)
        left = dummy_head
        right = dummy_head
        for i in range(n):
            right = right.next
        while right.next:
            left = left.next
            right = right.next
        left.next = left.next.next
        return dummy_head.next