class Test_Predictable_Stack_Top_With_4_Elements(unittest.TestCase):
def setUp(self):
self._stack = Stack()
self._stack.push(1)
self._stack.push(2)
self._stack.push(3)
self._stack.push(4)
def test_stack_top_with_4_elements(self):
self.assertEqual(self._stack.top, 4, 'NA')
def tearDown(self):
del self._stack
class Test_Iterator_With_Stack_Of_4_Elements(unittest.TestCase):
def setUp(self):
self._stack = Stack()
self._stack.push(1)
self._stack.push(2)
self._stack.push(3)
self._stack.push(4)
def test_iterator_with_stack_with_4_elements(self):
elements = [4, 3, 2, 1]
for stack_element in self._stack:
self.assertEqual(stack_element, elements[0],
'stack Iterator must match expected elements.')
del elements[0]
def tearDown(self):
del self._stack
def inorder_traversal_with_stack(self):
'''
this inorder traversal uses a stack and yields (key, value) pairs. this was added since link-
inversion traversal modifies the tree during traversal. This is a bummer as we use tree as a
hash bucket in hash tables. There are instances in MutableMapping where you iterate over the
key (tree has changed temporarily) and do d[key] which duly fails.
'''
stack = Stack()
current_node = self._root_node
while 1 == 1:
while(current_node != None):
stack.push(current_node)
current_node = current_node.left_child
if stack.size == 0:
break
popped_node = stack.pop()
yield (popped_node.key, popped_node.value)
current_node = popped_node.right_child
class Test_Pop_To_Empty_With_Predictable_Stack_Of_4_Elements(
unittest.TestCase):
def setUp(self):
self._stack = Stack()
self._stack.push(1)
self._stack.push(2)
self._stack.push(3)
self._stack.push(4)
def test_pop_to_empty_stack_with_4_elements(self):
self.assertEqual(self._stack.size, 4, 'NA')
elements = [4, 3, 2, 1]
for element in elements: #pop 4 times
self.assertEqual(self._stack.pop(), element)
self.assertEqual(self._stack.pop(), None,
'Empty stack must return None')
self.assertEqual(self._stack.size, 0, 'NA')
def tearDown(self):
del self._stack
'''
Created on Oct 25, 2015
@author: hari
'''
from __future__ import print_function
from builtins import str
from pycoils.stackNqueues.stack import Stack
if __name__ == '__main__':
stack = Stack()
# count items
print('stack items count: %s' % str(stack.size))
#Push items
stack.push(item=1)
stack.push(item=2)
stack.push(item=3)
stack.push(item=4)
stack.push(item=5)
stack.push(item=6)
#top
print('stack top is %s' % str(stack.top))
#pop
popped = stack.pop()
print('Popped item is %s' % str(popped))
#iterate over the stack popping items one by one
print('Iterate over stack popping items')
for item in stack:
print('item %s' % str(item))