def sumLists(list1Node, list2Node, carry=0):
if not (list1Node or list2Node or carry > 0):
return None
sumNode = Node(carry)
list1Next = None
list2Next = None
# Add the listNode only if necessary, this handles varying lengths
if list1Node:
sumNode.value += list1Node.value
list1Next = list1Node.next
if list2Node:
sumNode.value += list2Node.value
list2Next = list2Node.next
carry = sumNode.value / 10
sumNode.value = sumNode.value % 10
# hands off carry and next nodes of both lists recursively
nextSumNode = sumLists(list1Next, list2Next, carry)
# After node is received, take current node and put in front
sumNode.next = nextSumNode
return sumNode
def main():
########## testing single linked list
single_linked_list = SingleyLinkedList(Node(1))
single_linked_list.add_node(Node(2))
single_linked_list.add_node(Node(3))
single_linked_list.add_node(Node(4))
# single_linked_list.print()
# print(single_linked_list.tail.get_value())
# print(single_linked_list.cycle_check())
# single_linked_list.tail.next_node=single_linked_list.tail
# print(single_linked_list.cycle_check())
# single_linked_list.reverse_list()
#single_linked_list.print()
print(single_linked_list.nth_to_last_node(1))
single_linked_list.print()
print(single_linked_list.nth_to_last_node(3))
def test_index_of(self):
self.myList = LinkedList()
node1 = Node(1)
node2 = Node(2)
node3 = Node(3)
self.myList.head = node1
node1.next = node2
node2.next = node3
self.assertEqual(self.myList.index_of(1), 0)
self.assertEqual(self.myList.index_of(2), 1)
self.assertEqual(self.myList.index_of(3), 2)
self.assertFalse(self.l1.index_of(1))
self.assertFalse(self.l2.index_of(1))
self.assertEqual(self.l3.index_of(1), 0)
def recur_reverse(node: Node) -> Node:
"""Reverse a given linked list in-place.
:param l: A singly linked list class object
:type l: SinglyLinkedList
"""
if node is None or node.next is None:
return node
new_node = recur_reverse(node.next)
node.next.next = node
node.next = None
return new_node
def remove_duplicates_sorted_ii(llist):
sentinel = Node(0, llist.head)
pred = sentinel
head = llist.head
while head:
if head.next and head.val == head.next.val:
while head.next and head.val == head.next.val:
head = head.next
pred.next = head.next
else:
pred = pred.next
head = head.next
llist.head = sentinel.next
return
class NodeFunctionsTest(unittest.TestCase):
def setUp(self):
self.n1 = Node(1)
self.n2 = Node(2)
self.n3 = Node(3)
self.n3.next = self.n2
def test_get_data(self):
self.assertEqual(self.n1.get_data(), 1)
self.assertEqual(self.n3.get_data(), 3)
def test_get_next(self):
self.assertEqual(self.n1.get_next(), None)
self.assertEqual(self.n3.get_next(), self.n2)
def test_set_data(self):
self.n1.set_data(11)
self.assertEqual(self.n1.data, 11)
def test_set_next(self):
self.n2.set_next(self.n1)
self.assertEqual(self.n2.next, self.n1)
def intersects(ll1, ll2):
if ll1.getHead() == None or ll2.getHead() == None:
return False
current = ll1.getHead()
aux = {}
while current != None:
aux[current] = current
current = current.get_next()
current = ll2.getHead()
while current != None:
if current in aux.keys():
return True
current = current.get_next()
return False
ll1 = SinglyLinkedList()
inter = Node(5)
ll1.insert_node_at_beginning(inter)
ll1.insert_at_beginning(5)
ll1.insert_at_beginning(6)
ll2 = SinglyLinkedList()
ll2.insert_at_beginning(5)
ll2.insert_at_beginning(3)
ll2.insert_at_beginning(4)
print(intersects(ll1, ll2))
self.first = new_node
def remove(self, node):
if self.first.next == self.first:
self.first = None
else:
node.prev.next = node.next
node.next.prev = node.prev
if self.first == node:
self.first = node.next
def display(self):
if self.first is None:
return
current = self.first
while True:
print(current.data, end = ' ')
current = current.next
if current == self.first:
break
list = CircularDoublyLinkedList()
n1 = Node("Melanie")
n2 = Node("Andrew")
n3 = Node("Ronaldo")
n4 = Node("Mister")
list.insert_at_beg(n1)
list.insert_at_beg(n2)
list.insert_at_end(n4)
list.insert_at_end(n3)
list.display()
def setUp(self):
self.n1 = Node(1)
self.n2 = Node(2)
self.n3 = Node(3)
self.n3.next = self.n2
Implement an algorithm to delete a node in the middle of
a singly linked list given access only to that node
"""
from SinglyLinkedList import Node
#A cute trick, just copies the next node in the list
#removes the next node in the list, "deletes" itself
def removeNode(node):
if node.next:
node.value = node.next.value
node.next = node.next.next
else:
return None
headNode = Node(1, Node(2,
Node(3,
Node(4,
Node(5,
Node(6))))))
middleNode = headNode
for x in xrange(3):
middleNode = middleNode.next
print middleNode
headNode.printList()
removeNode(middleNode)
headNode.printList()
slow = linkedList._head fast = linkedList._head while slow is not None and slow._next is not None: slow = slow._next if fast is not None: fast = fast._next fast = fast._next else: return False if slow == fast: return True return False ll = SinglyLinkedList() n5 = Node(5) n4 = Node(4, n5) n3 = Node(3, n4) n2 = Node(2, n3) n1 = Node(1, n2) n5._next = n3 # setting the head to the created linked list ll._head = n1 # testing to see if the linked list loops curr = ll._head for i in range(8): print curr._element curr = curr._next
