def test_reverse_linked_list(linked_list):
"""Test that we reverse the list."""
from reverse_linked_list import reverse_linked_list
reverse_linked_list(linked_list)
assert linked_list.head.data == 1
assert linked_list.head.next_node.data == 2
assert linked_list.head.next_node.next_node.data == 3
def test_one_in_linked_list(linked_list):
"""Test get one time back with one item in list."""
from reverse_linked_list import reverse_linked_list
linked_list.pop()
linked_list.pop()
reverse_linked_list(linked_list)
assert linked_list.head.data == 1
def test_palindrome_method_1():
list1 = convert_array_to_linked_list(['f', 'g', 'e', 'g', 'f'])
list2 = reverse_linked_list(convert_array_to_linked_list(['f', 'g', 'e', 'g', 'f']))
naive_palindrome_check_by_comparing_list_and_reversed_list(list1, list2)
list3 = convert_array_to_linked_list(['a', 'g', 'e', 'd', 'f'])
list4 = reverse_linked_list(convert_array_to_linked_list(['a', 'g', 'e', 'd', 'f']))
naive_palindrome_check_by_comparing_list_and_reversed_list(list3, list4)
def test_empty_linked_list(linked_list):
"""Test exception from empty linked_list."""
from reverse_linked_list import reverse_linked_list
linked_list.pop()
linked_list.pop()
linked_list.pop()
with pytest.raises(IndexError):
reverse_linked_list(linked_list)
def method_1_reverse_linked_list_after_k(head, k):
temp_head = head
length = count_no_of_elements(head)
if k > length:
print "Wrong input: k value greater than length"
return
if not head:
print "list is empty"
return
count = 0
prev_head = None
while temp_head and count < k:
prev_head = temp_head
temp_head = temp_head.next
count += 1
print "\n head.contents:{0}".format(head)
print "\n prev head contents:{0}".format(prev_head)
print "\noriginal list: "
print_linked_list_contents(head)
reversed_k_head = reverse_linked_list(temp_head)
print "\n reversed_k_head list:"
print_linked_list_contents(reversed_k_head)
prev_head.next = reverse_linked_list
print "new::"
def test_convert_array_to_linked_list():
print "# convert array to a linked list"
head1 = convert_array_to_linked_list(['f', 'g', 'e', 'g', 'f'])
print_linked_list_contents(head1)
print "\n# reversed linked list"
# does not work
# reversed_head = head1
reversed_head = reverse_linked_list(convert_array_to_linked_list(['f', 'g', 'e', 'g', 'f']))
print_linked_list_contents(reversed_head)
def test_long_reverse_linked_list(linked_list):
"""Test that we reverse the list."""
from reverse_linked_list import reverse_linked_list
linked_list.push(4)
linked_list.push(5)
reverse_linked_list(linked_list)
assert linked_list.head.data == 1
assert linked_list.head.next_node.data == 2
assert linked_list.head.next_node.next_node.data == 3
assert linked_list.head.next_node.next_node.next_node.data == 4
assert linked_list.head.next_node.next_node.next_node.next_node.data == 5
assert linked_list.head.next_node.next_node.next_node.next_node.next_node is None
reverse_linked_list(linked_list)
assert linked_list.head.data == 5
assert linked_list.head.next_node.data == 4
assert linked_list.head.next_node.next_node.data == 3
assert linked_list.head.next_node.next_node.next_node.data == 2
assert linked_list.head.next_node.next_node.next_node.next_node.data == 1
assert linked_list.head.next_node.next_node.next_node.next_node.next_node is None
def test_one_element(self):
head = ListNode(1)
node = head
expected = [1]
for i in range(2, 10):
node.next = ListNode(i)
node = node.next
expected.insert(0, i)
self.assertEqual(
self.to_list(reverse_linked_list.reverse_linked_list(head)),
expected)
else:
lista.append(t_reversed_head.contents)
t_reversed_head = t_reversed_head.next
count = count + 1
lista.append(t_head.contents)
new_head = generate_linked_list_with_values(lista)
return new_head
if __name__ == "__main__":
head = generate_linked_list(6)
print "actual order :"
print_linked_list_contents(head)
print "\nexpected output: 1->6->2->5->3->4"
middle = middle_element_of_linked_list(head)
rest_reversed = reverse_linked_list(middle)
print "\nreversed :"
print_linked_list_contents(rest_reversed)
new_order = first_last_ordering_with_stack(head, rest_reversed, middle)
print "\nnew linked list order :"
print_linked_list_contents(new_order)
print "\nnew linked list order without stack:"
new_call = first_last_ordering_without_stack(head, rest_reversed, middle)
print_linked_list_contents(new_call)
# Empty case
print_linked_list_contents(first_last_ordering_with_stack(None, None, None))
print(head.value, end="")
while head.next != None:
head = head.next
print("-->" + str(head.value), end="")
print("")
def get_head():
head1 = Node(0)
head2 = Node(1, Node(2, Node(2, Node(3, Node(4, Node(5))))))
return head1, head2
if __name__ == '__main__':
# 移除指定值得节点, 考虑几种情况，1.只有一个节点的链表，2.初始节点的值为target，3.最后节点的值为target
head1, _ = get_head()
print_linked_list(remove_target_node(head1, 0))
head1, _ = get_head()
print_linked_list(remove_target_node(head1, 1))
_, head2 = get_head()
print_linked_list(remove_target_node(head2, 1))
_, head2 = get_head()
print_linked_list(remove_target_node(head2, 2))
_, head2 = get_head()
print_linked_list(remove_target_node(head2, 5))
# 翻转链表
head1, head2 = get_head()
print_linked_list(reverse_linked_list(head1))
print_linked_list(reverse_linked_list(head2))
def test_two_in_linked_list(linked_list):
"""Test that it works with two items."""
from reverse_linked_list import reverse_linked_list
linked_list.pop()
reverse_linked_list(linked_list)
assert linked_list.head.data == 1
