class Solution:
def __init__(self, *args):
self.single_link_list = SingleLinkList(None, *args)
print("初始化： ", end="")
self.single_link_list.travel()
def reverseKGroup(self, k):
start, end, self.next = self, self.single_link_list.head, self.single_link_list.head
has = 0
count = 1
while end: # 如果本节点不为空
if count == k:
prev, cur = start.next, start.next.next # 从start节点开始
while not (prev is end):
cur.next, prev, cur = prev, cur, cur.next
start.next.next, start.next, start = cur, prev, start.next
if not has:
self.next = end
has = 1
end = start.next
count = 1
else:
end = end.next # 指针往下走
count += 1 # 计数
self.single_link_list.travel(self.next)
def __init__(self, pos=-1, *args):
single_link_list = SingleLinkList(None, *args)
if 0 <= pos <= len(args) - 1:
count = 0
cur = single_link_list.head
while cur != None:
if count == pos:
break
else:
count += 1
cur = cur.next
single_link_list.tail.next = cur
self.single_link_list = single_link_list
# 通过快慢指针找到链表中点
slow = head
fast = head
# 每次循环快指针遍历2个结点，慢指针遍历1个结点
while fast and fast.next:
slow = slow.next
fast = fast.next.next
mid = slow # 找到中点结点
pre = None
while slow: # 后半段链表反转
slow.next, pre, slow = pre, slow, slow.next
# 反转后半段链表的头结点为pre，前半段链表的头结点为head
while head != mid: # 同时遍历两半段链表，直到中点；
if head.val != pre.val:
return False
head = head.next
pre = pre.next
return True
if __name__ == '__main__':
from single_link_list import SingleLinkList
sll = SingleLinkList()
for i in range(4):
sll.add_rear(i)
for i in range(3, -1, -1):
sll.add_rear(i)
sll.travel()
print(isPalindrome(sll.head))
print(isPalindrome2(sll.head))
def __init__(self, *k):
link_list = SingleLinkList(None, *k)
print("初始化： ", end=" ")
link_list.travel()
self.link_list = link_list
pre = head
head = head.next
pre.next = pre_pre
return pre
def reverse2(head):
pre = None
while head:
head.next, pre, head = pre, head, head.next
return pre
if __name__ == '__main__':
from single_link_list import SingleLinkList
ssl = SingleLinkList()
for i in range(2):
ssl.add_rear(i)
ssl.travel()
head = reverse_list(ssl.head)
ssl2 = SingleLinkList(head)
ssl2.travel()
ss3 = SingleLinkList()
for i in range(5):
ss3.add_rear(i)
ss3.travel()
head = reverse2(ss3.head)
ss4 = SingleLinkList(head)
ss4.travel()
def removeNthFromEnd(self, head: ListNode, n: int) -> ListNode:
dummy = ListNode(0)
dummy.next = head
slow = fast = dummy
while n:
fast = fast.next
n -= 1
while fast.next:
slow = slow.next
fast = fast.next
slow.next = slow.next.next
return dummy.next
if __name__ == '__main__':
sll = SingleLinkList()
for i in range(2):
sll.add_rear(i + 1)
new_sll = SingleLinkList(removeNthFromEnd(sll.head, 1))
new_sll.travel()
sll2 = SingleLinkList()
for i in range(2):
sll2.add_rear(i + 1)
ns = SingleLinkList(remove2(sll2.head, 2))
ns.travel()
sll3 = SingleLinkList()
for i in range(2):
sll3.add_rear(i + 1)
ns = SingleLinkList(remove3(sll3.head, 1))
head.next = ListNode(sum_val)
head = head.next
l1 = l1.next
while l2:
sum_val = l2.val + flag
if sum_val >= 10:
sum_val %= 10
flag = 1
else:
flag = 0
head.next = ListNode(sum_val)
head = head.next
l2 = l2.next
if flag:
head.next = ListNode(1)
return dummy.next
if __name__ == '__main__':
from single_link_list import SingleLinkList
s1 = SingleLinkList()
s2 = SingleLinkList()
for i in range(1, 2):
s1.add_rear(i)
s2.add_rear(9)
s2.add_rear(9)
# s = SingleLinkList(addTwoNumbers(s1.head, s2.head))
s = SingleLinkList(addt(s1.head, s2.head))
s.travel()
def __init__(self, *args):
self.single_link_list = SingleLinkList(None, *args)
print("初始化： ", end="")
self.single_link_list.travel()