题解 | #输出单向链表中倒数第k个结点#

class Node(object):
    def __init__(self,data, next = None):
        self.data = data
        self.next = next

class LinkList(object):
    def __init__(self, node=None):
        self.__head = None

    def isempty(self):
        return self.__head==None
    
    def append(self,item):
        node = Node(item)
        if self.isempty():
            self.__head = node
        else:
            cur = self.__head
            while cur.next != None:
                cur = cur.next
            cur.next = node

    def pos_search(self,long,pos):
        cur = self.__head
        cur_c = 0
        if pos <= 0:
            print("0")
            return False
        else:
            while cur != None:
                cur_c += 1
                if cur_c == (long-pos+1):
                    print(cur.data)
                    return True
                else:
                    cur = cur.next
            return False
    
if __name__ == "__main__":
    while True:
        try:
            long = int(input())
            string = input()
            pos = int(input())
            item = string.split(" ")
            ll = LinkList()
            for i in range(long):
                n = item[i]
                ll.append(n)
            ll.pos_search(long, pos)
                          
        except:
             break