def addTwoNumbers(self, l1, l2):
"""
:type l1: ListNode
:type l2: ListNode
:rtype: ListNode
"""
if not l1:
return l2
if not l2:
return l1
dummy_node = SingleLinkedNode()
node = dummy_node
carry = 0
while l1 is not None or l2 is not None or carry != 0:
if l1 is not None:
carry += l1.value
l1 = l1.next
if l2 is not None:
carry += l2.value
l2 = l2.next
temp_node = SingleLinkedNode()
temp_node.value = carry % 10
node.next = temp_node
node = node.next
carry = carry // 10
return dummy_node.next
def addTwoNumbers2(self, l1, l2):
"""
:type l1: ListNode
:type l2: ListNode
:rtype: ListNode
"""
if not l1:
return l2
if not l2:
return l1
stack_l1 = deque()
while l1 is not None:
stack_l1.append(l1.value)
l1 = l1.next
stack_l2 = deque()
while l2 is not None:
stack_l2.append(l2.value)
l2 = l2.next
dummy_node = None
carry = 0
while len(stack_l1) != 0 or len(stack_l2) != 0 or carry != 0:
if len(stack_l1) != 0:
carry += stack_l1.pop()
if len(stack_l2) != 0:
carry += stack_l2.pop()
new_node = SingleLinkedNode()
new_node.value = carry % 10
new_node.next = dummy_node
dummy_node = new_node
carry //= 10
return dummy_node
def mergeTwoLists(self, l1, l2):
"""
:type l1: ListNode
:type l2: ListNode
:rtype: ListNode
"""
if l1 is None:
return l2
if l2 is None:
return l1
dummy_node = SingleLinkedNode()
node = dummy_node
while l1 is not None and l2 is not None:
if l1.value < l2.value:
node.next = l1
l1 = l1.next
else:
node.next = l2
l2 = l2.next
node = node.next
if l1 is None:
node.next = l2
else:
node.next = l1
return dummy_node.next
def swapPairs_iteration(self, head):
dummy = pre = SingleLinkedNode()
pre.next = head
while pre.next and pre.next.next:
a = pre.next
b = a.next
pre.next, a.next, b.next = b, b.next, a
pre = a
return dummy.next
def test_swapPairs_one_node_iteration(self):
input_node = SingleLinkedNode()
input_node.value = 1
head = self.solution.swapPairs(input_node)
self.assertEqual(input_node, head)
def test_removeNthFromEnd_1element_k_equals_1(self):
input_node = SingleLinkedNode()
input_node.value = 1
head = self.solution.removeNthFromEnd(input_node, 1)
self.assertIsNone(head)
def test_reverseList_iterate_single_node(self):
input_node = SingleLinkedNode()
node = self.solution.reverseList_iteration(input_node)
self.assertEqual(input_node, node)