class ListStack:
# TODO limit size
def __init__(self, size=0):
self.list_obj = LinkedList()
# top of the stack is
def list(self):
return [link.key for link in self.list_obj.array()]
def isEmpty(self):
return self.list_obj.isEmpty()
def push(self, key):
self.list_obj.insertFirst(key, None)
def pop(self):
if self.isEmpty():
raise ValueError("Popping from empty stack")
return self.list_obj.deleteFirst().key
def peek(self):
if self.isEmpty():
raise ValueError("Peeking from empty stack")
return self.list_obj.first.key
def test_delete_non_existing(self):
list = LinkedList()
list.insertFirst(1, {"a": 1})
list.insertFirst(2, {"b": 2})
list.insertFirst(3, {"c": 3})
self.assertEqual(list.delete(2).data["b"], 2)
self.assertEqual(len(list.array()), 2)
def test_delete_existing(self):
list = LinkedList()
list.insertFirst(1, {"a": 1})
list.insertFirst(2, {"b": 2})
list.insertFirst(3, {"c": 3})
self.assertEqual(list.delete(4), None)
self.assertEqual(len(list.array()), 3)
def sort(self, array):
list = LinkedList()
for i in range(len(array)):
if list.isEmpty():
list.insertFirst(array[i], None)
else:
prev, curr = None, list.first
while (curr != None and curr.key < array[i]):
prev, curr = curr, curr.next
node = Link(array[i], None, curr)
if prev == None:
list.first = node
else:
prev.next = node
return [link.key for link in list.array()]
def test_delete_first_non_empty(self):
list = LinkedList()
list.insertFirst(1, {"a": 1})
list.insertFirst(2, {"b": 2})
self.assertEqual(list.deleteFirst().data["b"], 2)
self.assertEqual(len(list.array()), 1)
