def sum_lists(ll_a, ll_b):
n1, n2 = ll_a.head, ll_b.head
ll = LinkedList()
carry = 0
while n1 or n2:
result = carry
if n1:
result += n1.value
n1 = n1.next
if n2:
result += n2.value
n2 = n2.next
ll.add(result % 10)
carry = result // 10
if carry:
ll.add(carry)
return ll
from chapter_02.linked_list import LinkedList
def delete_middle_node(node):
node.value = node.next.value
node.next = node.next.next
if __name__ == "__main__":
ll = LinkedList()
ll.add_multiple([1, 2, 3, 4])
middle_node = ll.add(5)
ll.add_multiple([7, 8, 9])
print(ll)
delete_middle_node(middle_node)
print(ll)
