def find_lask_k(head, k):
if head is None or head.next is None:
return head
slow = LNode()
fast = LNode()
slow = head.next
fast = head.next
i = 0
while i < k and fast is not None:
fast = fast.next
i += 1
if i < k: #不够长
return None
while fast is not None:
slow = slow.next
fast = fast.next
return slow
def my_has_loop(head)->bool:
#破坏型判断是否有环
if head is None or head.next is None:
return False
cur = head.next
flag = LNode(0)
while cur:
if cur.next is flag:
return True
temp = cur.next
cur.next = flag
cur = temp
return False
def ConstructList():
i = 1
head = LNode()
head.next = None
tmp = None
cur = head
# 构造第一个链表
while i < 8:
tmp = LNode()
tmp.data = i
tmp.next = None
cur.next = tmp
cur = tmp
i += 1
return head
cur=next
while cur.next!=None:
next=cur.next
cur.next=pre
pre=cur
cur=cur.next
cur=next
cur.next = pre # 最后一个节点指向倒数第二个节点
head.next = cur
if __name__ == '__main__':
i=1
head=LNode(None)
head.next=None
tmp=None
cur=head
while i<8:
tmp=LNode(i)
tmp.next=None
cur.next=tmp
cur=tmp
i+=1
print("逆序前：")
cur=head.next
while cur is not None:
print(cur.data)
cur=cur.next
def add(h1, h2):
if h1 is None or h1.next is None:
return h2
if h2 is None or h2.next is None:
return h1
c=0#记录进位
sums=0#记录两个节点相加的值
p1=h1.next
p2=h2.next
tmp=None#存储相加的和
resultHead=LNode()#相加后的链表的头节点
resultHead.next=None
p=resultHead#用来指向链表resultHead最后一个节点
while p1 is not None and p2 is not None:
tmp=LNode()
sums=p1.data + p2.data + c
tmp.data=sums % 10
c=int(sums/10)
p.next = tmp#加入新链表
p=tmp
p1=p1.next
p2=p2.next
#p2比p1长,p1比p2长
if p1 is None:
while p2 is not None:
tmp=LNode()
sums=p2.data+c
tmp.data=sums%10
c=int(sums/10)
p.next=tmp
p=tmp
p2=p2.next
if p2 is None:
while p1 is not None:
tmp=LNode()
sums=p1.data+c
tmp.data=sums%10
c=int(sums/10)
p.next=tmp
p=tmp
p1=p1.next
#完成全部计算后还有进位
if c==1:
tmp=LNode()
tmp.data=1
p.next=tmp
return resultHead
sums=p1.data+c
tmp.data=sums%10
c=int(sums/10)
p.next=tmp
p=tmp
p1=p1.next
#完成全部计算后还有进位
if c==1:
tmp=LNode()
tmp.data=1
p.next=tmp
return resultHead
if __name__ == '__main__':
i = 1
head1 = LNode()
head1.next = None
head2 = LNode()
head2.next = None
tmp = None
cur = head1
addResult = None
# 构造第一个链表
while i < 7:
tmp = LNode()
tmp.data = i + 2
tmp.next = None
cur.next = tmp
cur = tmp
i += 1
cur = head2
inner_pre = None
while out_cur is not None:
inner_cur = out_cur.next
inner_pre = out_cur
while inner_cur is not None:
if inner_cur.data == out_cur.data:
inner_pre.next = inner_cur.next
else:
inner_pre = inner_cur
inner_cur = inner_cur.next
out_cur = out_cur.next
if __name__ == '__main__':
i = 1
head = LNode()
tmp = None
cur = head
while i < 7:
tmp = LNode()
if i % 2 == 0:
tmp.data = i + 1
elif i % 3 == 0:
tmp.data = i - 2
else:
tmp.data = i
tmp.next = None
cur.next = tmp
cur = tmp
i += 1
print("删除前：")
else:
return #剩余节点数小于k
end_next = end.next
end.next = None #断开链接逆序k个元素内部
pre.next = reverse(begin)
begin.next = end_next
#逆序完成后，回到上次相同的指针状态
pre = begin
begin = begin.next
i = 1
if __name__ == "__main__":
i = 1
head = LNode()
head.next = None
tmp = None
cur = head
while i < 8:
tmp = LNode()
tmp.data = i
tmp.next = None
cur.next = tmp
cur = tmp
i += 1
print("顺序输出：", end='')
cur = head.next
while cur != None:
print(cur.data, end=' ')
def remove_node(p):
if p.next is None or p is None:
return False #无法删除
p_next = p.next
next = p.next.next
p.data = p_next.data
p.next = next
p_next.next = None
return True
if __name__ == "__main__":
i = 1
head = LNode() # 链表头结点
head.next = None
tmp = None
cur = head
p = None
# 构造链表
while i < 8:
tmp = LNode()
tmp.data = i
tmp.next = None
cur.next = tmp
cur = tmp
if i == 5:
p = tmp
i += 1
print("删除结点" + str(p.data) + "前链表: ")