if node_list[i] != node_list[j]:
return False
i += 1
j -= 1
return True
def is_palindrome(self, head: ListNode) -> bool:
'''
返回交点
Args:
head: 节点head
Returns:
布尔值
'''
node_list = []
if not head:
return True
while head:
node_list.append(head.val)
head = head.next
return self.is_palindrome_list(node_list)
if __name__ == '__main__':
arr = [1, 2, 3, 3, 2, 1]
list_node = ListNode()
head = list_node.create_list_node_array(arr)
solution = Solution()
result = solution.is_palindrome(head)
print(result)
return self.add_two_number_helper(l1, l2, 0)
def add_two_number_helper(self, l1: ListNode, l2: ListNode,
v: 0) -> ListNode:
'''
相加帮助类
Args:
l1: l1链表
l2: l2链表
v: 值
Returns:
链表
'''
if not l1 and not l2:
return None if v == 0 else ListNode(v)
if l1:
v += l1.val
l1 = l1.next
if l2:
v += l2.val
l2 = l2.val
return ListNode(v % 10, self.add_two_number_helper(l1, l2, v / 10))
if __name__ == '__main__':
l1 = ListNode.create_list_node_array([1, 2, 3])
l2 = ListNode.create_list_node_array([2, 3, 4])
solution = Solution()
result = solution.add_two_number(l1, l2)
print(result)
def merge_two_lists_2(self, l1: ListNode, l2: ListNode) -> ListNode:
'''
合并两个链表
Args:
l1: l1链表
l2: l2链表
Returns:
合并后的链表
'''
if not l1:
return l2
if not l2:
return l1
if l1.val <= l2.val:
l1.next = self.merge_two_lists_2(l1.next, l2)
return l1
else:
l2.next = self.merge_two_lists_2(l1, l2.next)
return l2
if __name__ == '__main__':
list_node = ListNode()
l1 = list_node.create_list_node_array([1, 2, 4])
l2 = list_node.create_list_node_array([1, 3, 4, 5])
solution = Solution()
result = solution.merge_two_lists_2(l1, l2)
print(result.val)
assert result.val == 1
class Solution:
def get_intersection_node(self, head_a: ListNode,
head_b: ListNode) -> ListNode:
'''
返回交点
Args:
head_a: 链表a
head_b: 链表b
Returns:
交点
'''
if not head_a or not head_b:
return None
p_A = head_a
p_B = head_b
while p_A != p_B:
p_A = head_b if not p_A else p_A.next
p_B = head_a if not p_B else p_B.next
return p_A
if __name__ == '__main__':
arr1 = [4, 1, 8, 4, 5]
l1 = ListNode.create_list_node_array(arr1)
arr2 = [5, 0, 1, 8, 4, 5]
l2 = ListNode.create_list_node_array(arr2)
solution = Solution()
result = solution.get_intersection_node(l1, l2)
print(result)
assert result == None