class Stack:
def __init__(self):
self.s = LinkedList()
self.head = self.s.sentinel
def push(self, x):
newnode = Node(x)
self.s.insert(newnode)
def pop(self):
x = self.s.head
if x is None:
raise UnderFlowError
self.s.delete(self.s.head)
return x
class Stack(object):
def __init__(self):
self.S = SinglyLinkedList()
def is_empty(self):
return self.S.is_empty()
def push(self, element):
self.S.insert(SinglyLinkedListNode(element)) # Linked list implementation of stack overflow do not exist
def pop(self):
head_node = self.S.delete_head()
if head_node:
return head_node.key
else:
raise IndexError('stack underflow')
from singly_linked_list import SinglyLinkedList
my_list = SinglyLinkedList()
my_list.print()
for i in range(10):
my_list.append(i + 1)
my_list.print()
for i in range(10):
my_list.prepend(i + 1)
my_list.print()
value = my_list.access(3)
print('my_list.access(3) = ' + str(value))
my_list.insert(8, 128)
my_list.print()
my_list.remove(4)
my_list.print()
my_list.set_head(10)
my_list.print()
def test_insert(self):
ls = SinglyLinkedList()
ls.append("a").append("b").append("d")
ls.insert(2, "c")
self.assertEqual("c", ls.head.next.next.value)
def test_insert_filled_index_0(self):
linkedlist = SinglyLinkedList([1, 2, 3, 4, 5])
linkedlist.insert(0, 99)
assert linkedlist[0] == 99
assert len(linkedlist) == 6
def test_insert_from_empty(self):
linkedlist = SinglyLinkedList()
with pytest.raises(IndexError):
linkedlist.insert(0, 0)
