leetcode之Reverse Linked List II

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
def reverseBetween(self, head, m, n):
"""
:type head: ListNode
:type m: int
:type n: int
:rtype: ListNode
"""
if not head:
return head
if not head.next:
return head
if m == n:
return head
listofNode = []
length = head
num = 0
while length:
if m == 1:
num += 1
listofNode.append(length)
length = length.next
if num == n:
head = listofNode[-1]
for i in range(len(listofNode) - 1)[::-1]:
listofNode[i + 1].next = listofNode[i]
listofNode[0].next = length

else:
num += 1
if num == m - 1:
b = length

elif num == m:
listofNode.append(length)
elif num < n and num > m:
listofNode.append(length)
else:
if num == n:
listofNode.append(length)
listofNode[0].next = listofNode[-1].next
b.next = listofNode[-1]
for i in range(len(listofNode) - 1)[::-1]:
listofNode[i + 1].next = listofNode[i]
if length:
length = length.next
return head