def reverse_and_compare(node):
original_head = node
# Reverse linked list
reversed_head = None
while node:
new_node = Node(node.val)
new_node.next = reversed_head
reversed_head = new_node
node = node.next
# Compare
while original_head or reversed_head:
if original_head.val != reversed_head.val:
return False
original_head = original_head.next
reversed_head = reversed_head.next
return reversed_head is None and original_head is None
def backward_solution(first, second, carry=0):
if first is None and second is None and carry == 0:
return None
result = Node(None)
value = carry
if first is not None:
value += first.val
if second is not None:
value += second.val
# Last digit of number
result.val = value % 10
if first is not None or second is not None:
next_node = backward_solution(first and first.next, second
and second.next, 1 if value >= 10 else 0)
result.next = next_node
return result
def _get_kth_node(node, kth):
while kth > 0 and node:
node = node.next
kth -= 1
return node
def insert_after(head, value, node):
while head:
if head.val == value:
head.next = node
head = head.next
if __name__ == "__main__":
first = create_list([0, 1, 2, 3, 4, 5, 6, 7])
second = create_list([11, 12, 13, 14])
intersecting_node = Node(-1)
intersecting_node.next = Node(-2)
intersecting_node.next.next = Node(-3)
insert_after(first, 7, intersecting_node)
insert_after(second, 14, intersecting_node)
print(f"Solution({first}, {second}) -> ",
brute_force_solution(first, second))
print(f"Solution({first}, {second}) -> ",
count_and_compare_solution(first, second))