题解 | #从单向链表中删除指定值的节点#

class Node(object):
    def __init__(self, elem):

        self.elem = elem
        self.next = None

class SingleLinkList(object):
    def __init__(self,node=None):
        self._head = node

    def is_empty(self):
        return self._head == None

    def length(self):
        cur = self._head
        count = 0
        while cur != None:
            count += 1
            cur = cur.next
        return count

    def travel(self):
        cur = self._head
        while cur != None:
            print(cur.elem)
            cur = cur.next

    def add(self,item):
        node = Node(item)
        node.next = self._head
        self._head = node

    def append(self,item):
        node = Node(item)
        if self.is_empty():
            self._head = node
        else:
            cur = self._head
            while cur.next != None:
                cur = cur.next
            cur.next = node
        

    def insert(self,pos,item):
        if pos <= 0:
            self.add(item)
        if pos > (self.length()-1):
            self.append(item)
        else:
            pre = self._head
            count = 0
            node = Node(item)
            while count <(pos - 1):
                count += 1
                pre = pre.next
            node.next = pre.next
            pre.next = node

    def remove(self,item):
        cur = self._head
        pre = None
        while cur != None:
            if cur.elem == item:
                if cur == self._head:
                    self._head = cur.next
                else:
                    pre.next = cur.next
                break
            else:
                pre = cur
                cur = cur.next

    def search(self,item):
        cur = self._head
        while cur != None:
            if cur.elem == item:
                return True
            else:
                cur = cur.next
        return False
    
    def insert_m_after_n(self,m,n):
        cur = self._head
        while cur != None:
            if cur.elem == n:
                if cur.next == None:
                    self.append(m)
                else:
                    node = Node(m)
                    node.next = cur.next
                    cur.next = node
                break
            else:
                cur = cur.next
        
    def zhuanzifuchuan(self):
        cur = self._head
        sty = ""
        while cur != None:
            sty = sty + str(cur.elem) + " "
            cur = cur.next
        return sty


if __name__ == "__main__":
    ll = SingleLinkList()
    stry = input().split()
    n = int(stry[0])
    ll.add(int(stry[1]))
    for i in range(n-1):
        ll.insert_m_after_n(int(stry[i*2+2]),int(stry[i*2+3]))
    ll.remove(int(stry[-1]))
    
    print(ll.zhuanzifuchuan())