class StackAsLinkedList(Stack):
"""
Stack implemented using a linked list.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self):
"""
(StackAsLinkedList)
Constructs a stack.
"""
super(StackAsLinkedList, self).__init__()
self._list = LinkedList()
def purge(self):
"""
(StackAsLinkedList) -> None
Purges this stack.
"""
self._list.purge()
self._count = 0
#}>a
#{
def push(self, obj):
"""
(StackAsLinkedList, Object) -> None
Pushes the given object on to this stack.
"""
self._list.prepend(obj)
self._count += 1
def pop(self):
"""
(StackAsLinkedList) -> None
Pops the top object off this stack.
"""
if self._count == 0:
raise ContainerEmpty
result = self._list.first
self._list.extract(result)
self._count -= 1
return result
def getTop(self):
"""
(StackAsLinkedList) -> None
Returns the object at the top of this stack.
"""
if self._count == 0:
raise ContainerEmpty
return self._list.first
#}>b
#{
def accept(self, visitor):
"""
(StackAsLinkedList, Visitor) -> None
Makes the given visitor visit all the objects in this stack.
"""
assert isinstance(visitor, Visitor)
ptr = self._list.head
while ptr is not None:
visitor.visit(ptr.datum)
if visitor.isDone:
return
ptr = ptr.next
#}>c
#{
class Iterator(Iterator):
"""
Enumerates the elements of a StackAsLinkedList.
"""
def __init__(self, stack):
"""
(StackAsLinkedList.Iterator, StackAsLinkedList) -> None
Constructs an iterator for the given stack.
"""
super(StackAsLinkedList.Iterator, self).__init__(stack)
self._position = stack._list.head
def next(self):
"""
(StackAsLinkedList.Iterator) -> Object
Returns the next element.
"""
if self._position is None:
raise StopIteration
element = self._position
self._position = self._position.next
return element.datum
def __iter__(self):
"""
(StackAsLinkedList) -> StackAsLinkedList.Iterator
Returns an iterator for this stack.
"""
return self.Iterator(self)
#}>d
def _compareTo(self, obj):
"""
(StackAsLinkedList, StackAsLinkedList) -> int
Compares this stack with the given stack.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
@staticmethod
def main(*argv):
"StackAsLinkedList test program."
print StackAsLinkedList.main.__doc__
stack2 = StackAsLinkedList()
Stack.test(stack2)
return 0
class GeneralTree(Tree):
"""
A general tree implemented using a linked list of subtrees.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self, key):
"""
(GeneralTree, Object) -> None
Constructs a general tree with the given object at its root.
"""
super(GeneralTree, self).__init__()
self._key = key
self._degree = 0
self._list = LinkedList()
def purge(self):
"""
(GeneralTree) -> None
Purges this general tree.
"""
self._list.purge()
self._degree = 0
#}>a
def getIsEmpty(self):
"""
(GeneralTree) -> bool
Returns false always.
"""
return False
def getIsLeaf(self):
"""
(GeneralTree) -> bool
Returns true if this general tree is a leaf.
"""
return self._degree == 0
def getDegree(self):
"""
(GeneralTree) -> int
Returns the degree of this general tree node.
"""
return self._degree
#{
def getKey(self):
"""
(GeneralTree) -> Object
Returns the key in this general tree node.
"""
return self._key
def getSubtree(self, i):
"""
(GeneralTree) -> Object
Returns the specified subtree of this general tree node.
"""
if i < 0 or i >= self._degree:
raise IndexError
ptr = self._list.head
for j in xrange(i):
ptr = ptr.next
return ptr.datum
def attachSubtree(self, t):
"""
(GeneralTree, GeneralTree) -> None
Attaches the given general tree as a subtree
of this general tree node.
"""
self._list.append(t)
self._degree += 1
def detachSubtree(self, t):
"""
(GeneralTree, GeneralTree) -> GeneralTree
Detaches and returns specified general tree
from this general tree node.
"""
self._list.extract(t)
self._degree -= 1
return t
#}>b
def _compareTo(self, obj):
"""
(GeneralTree, GeneralTree) -> int
Compares this general tree with the given general tree.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
@staticmethod
def main(*argv):
"GeneralTree test program."
print GeneralTree.main.__doc__
gt = GeneralTree('A')
gt.attachSubtree(GeneralTree('B'))
gt.attachSubtree(GeneralTree('C'))
gt.attachSubtree(GeneralTree('D'))
gt.attachSubtree(GeneralTree('E'))
Tree.test(gt)
return 0
class GeneralTree(Tree):
"""
A general tree implemented using a linked list of subtrees.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self, key):
"""
(GeneralTree, Object) -> None
Constructs a general tree with the given object at its root.
"""
super(GeneralTree, self).__init__()
self._key = key
self._degree = 0
self._list = LinkedList()
def purge(self):
"""
(GeneralTree) -> None
Purges this general tree.
"""
self._list.purge()
self._degree = 0
#}>a
def getIsEmpty(self):
"""
(GeneralTree) -> bool
Returns false always.
"""
return False
def getIsLeaf(self):
"""
(GeneralTree) -> bool
Returns true if this general tree is a leaf.
"""
return self._degree == 0
def getDegree(self):
"""
(GeneralTree) -> int
Returns the degree of this general tree node.
"""
return self._degree
#{
def getKey(self):
"""
(GeneralTree) -> Object
Returns the key in this general tree node.
"""
return self._key
def getSubtree(self, i):
"""
(GeneralTree) -> Object
Returns the specified subtree of this general tree node.
"""
if i < 0 or i >= self._degree:
raise IndexError
ptr = self._list.head
for j in xrange(i):
ptr = ptr.next
return ptr.datum
def attachSubtree(self, t):
"""
(GeneralTree, GeneralTree) -> None
Attaches the given general tree as a subtree
of this general tree node.
"""
self._list.append(t)
self._degree += 1
def detachSubtree(self, t):
"""
(GeneralTree, GeneralTree) -> GeneralTree
Detaches and returns specified general tree
from this general tree node.
"""
self._list.extract(t)
self._degree -= 1
return t
#}>b
def _compareTo(self, obj):
"""
(GeneralTree, GeneralTree) -> int
Compares this general tree with the given general tree.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
@staticmethod
def main(*argv):
"GeneralTree test program."
print GeneralTree.main.__doc__
gt = GeneralTree('A')
gt.attachSubtree(GeneralTree('B'))
gt.attachSubtree(GeneralTree('C'))
gt.attachSubtree(GeneralTree('D'))
gt.attachSubtree(GeneralTree('E'))
Tree.test(gt)
return 0
class QueueAsLinkedList(Queue):
"""
Queue implemented using a linked list.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self):
"""
(QueueAsLinkedList) -> None
Constructs a queue.
"""
super(QueueAsLinkedList, self).__init__()
self._list = LinkedList()
def purge(self):
"""
(QueueAsLinkedList) -> None
Purges this queue.
"""
self._list.purge()
self._count = 0
#}>a
#{
def getHead(self):
"""
(QueueAsLinkedList) -> Object
Returns the object at the head of this queue.
"""
if self._count == 0:
raise ContainerEmpty
return self._list.first
def enqueue(self, obj):
"""
(QueueAsLinkedList, Object) -> None
Enqueues the given object to the tail of this queue.
"""
self._list.append(obj)
self._count += 1
def dequeue(self):
"""
(QueueAsLinkedList) -> Object
Dequeues the object at the head of this queue.
"""
if self._count == 0:
raise ContainerEmpty
result = self._list.first
self._list.extract(result)
self._count -= 1
return result
#}>b
def accept(self, visitor):
"""
(QueueAsLinkedList, Visitor) -> None
Makes the given visitor visit all the objects in this queue.
"""
assert isinstance(visitor, Visitor)
ptr = self._list.head
while ptr is not None:
visitor.visit(ptr.datum)
if visitor.isDone:
return
ptr = ptr.next
class Iterator(Iterator):
"""
Enumerates the elements of a QueueAsLinkedList.
"""
def __init__(self, queue):
"""
(QueueAsLinkedList.Iterator, QueueAsLinkedList) -> None
Constructs an iterator for the given queue.
"""
super(QueueAsLinkedList.Iterator).__init__(queue)
self._position = None
def next(self):
"""
(QueueAsLinkedList.Iterator) -> Object
Returns the next element.
"""
if self._position is None:
self._position = self._container._list.head
else:
self._position = self._position.next
if self._position is None:
raise StopIteration
return self._position.datum
def __iter__(self):
"""
(QueueAsLinkedList) -> QueueAsLinkedList.Iterator
Returns an iterator for this queue.
"""
return self.Iterator(self)
def _compareTo(self, obj):
"""
(QueueAsLinkedList, QueueAsLinkedList) -> int
Comparse this queue with the given queue.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
@staticmethod
def main(*argv):
"QueueAsLinkedList test program."
print QueueAsLinkedList.main.__doc__
queue2 = QueueAsLinkedList()
Queue.test(queue2)
return 0
class QueueAsLinkedList(Queue):
"""
Queue implemented using a linked list.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self):
"""
(QueueAsLinkedList) -> None
Constructs a queue.
"""
super(QueueAsLinkedList, self).__init__()
self._list = LinkedList()
def purge(self):
"""
(QueueAsLinkedList) -> None
Purges this queue.
"""
self._list.purge()
self._count = 0
#}>a
#{
def getHead(self):
"""
(QueueAsLinkedList) -> Object
Returns the object at the head of this queue.
"""
if self._count == 0:
raise ContainerEmpty
return self._list.first
def enqueue(self, obj):
"""
(QueueAsLinkedList, Object) -> None
Enqueues the given object to the tail of this queue.
"""
self._list.append(obj)
self._count += 1
def dequeue(self):
"""
(QueueAsLinkedList) -> Object
Dequeues the object at the head of this queue.
"""
if self._count == 0:
raise ContainerEmpty
result = self._list.first
self._list.extract(result)
self._count -= 1
return result
#}>b
def accept(self, visitor):
"""
(QueueAsLinkedList, Visitor) -> None
Makes the given visitor visit all the objects in this queue.
"""
assert isinstance(visitor, Visitor)
ptr = self._list.head
while ptr is not None:
visitor.visit(ptr.datum)
if visitor.isDone:
return
ptr = ptr.next
class Iterator(Iterator):
"""
Enumerates the elements of a QueueAsLinkedList.
"""
def __init__(self, queue):
"""
(QueueAsLinkedList.Iterator, QueueAsLinkedList) -> None
Constructs an iterator for the given queue.
"""
super(QueueAsLinkedList.Iterator).__init__(queue)
self._position = None
def next(self):
"""
(QueueAsLinkedList.Iterator) -> Object
Returns the next element.
"""
if self._position is None:
self._position = self._container._list.head
else:
self._position = self._position.next
if self._position is None:
raise StopIteration
return self._position.datum
def __iter__(self):
"""
(QueueAsLinkedList) -> QueueAsLinkedList.Iterator
Returns an iterator for this queue.
"""
return self.Iterator(self)
def _compareTo(self, obj):
"""
(QueueAsLinkedList, QueueAsLinkedList) -> int
Comparse this queue with the given queue.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
def main(*argv):
"QueueAsLinkedList test program."
print QueueAsLinkedList.main.__doc__
queue2 = QueueAsLinkedList()
Queue.test(queue2)
return 0
main = staticmethod(main)
class StackAsLinkedList(Stack):
"""
Stack implemented using a linked list.
"""
#}@head
#{
# ...
#}@tail
#{
def __init__(self):
"""
(StackAsLinkedList)
Constructs a stack.
"""
super(StackAsLinkedList, self).__init__()
self._list = LinkedList()
def purge(self):
"""
(StackAsLinkedList) -> None
Purges this stack.
"""
self._list.purge()
self._count = 0
#}>a
#{
def push(self, obj):
"""
(StackAsLinkedList, Object) -> None
Pushes the given object on to this stack.
"""
self._list.prepend(obj)
self._count += 1
def pop(self):
"""
(StackAsLinkedList) -> None
Pops the top object off this stack.
"""
if self._count == 0:
raise ContainerEmpty
result = self._list.first
self._list.extract(result)
self._count -= 1
return result
def getTop(self):
"""
(StackAsLinkedList) -> None
Returns the object at the top of this stack.
"""
if self._count == 0:
raise ContainerEmpty
return self._list.first
#}>b
#{
def accept(self, visitor):
"""
(StackAsLinkedList, Visitor) -> None
Makes the given visitor visit all the objects in this stack.
"""
assert isinstance(visitor, Visitor)
ptr = self._list.head
while ptr is not None:
visitor.visit(ptr.datum)
if visitor.isDone:
return
ptr = ptr.next
#}>c
#{
class Iterator(Iterator):
"""
Enumerates the elements of a StackAsLinkedList.
"""
def __init__(self, stack):
"""
(StackAsLinkedList.Iterator, StackAsLinkedList) -> None
Constructs an iterator for the given stack.
"""
super(StackAsLinkedList.Iterator, self).__init__(
stack)
self._position = stack._list.head
def next(self):
"""
(StackAsLinkedList.Iterator) -> Object
Returns the next element.
"""
if self._position is None:
raise StopIteration
element = self._position
self._position = self._position.next
return element.datum
def __iter__(self):
"""
(StackAsLinkedList) -> StackAsLinkedList.Iterator
Returns an iterator for this stack.
"""
return self.Iterator(self)
#}>d
def _compareTo(self, obj):
"""
(StackAsLinkedList, StackAsLinkedList) -> int
Compares this stack with the given stack.
"""
assert isinstance(self, obj.__class__)
raise NotImplementedError
@staticmethod
def main(*argv):
"StackAsLinkedList test program."
print StackAsLinkedList.main.__doc__
stack2 = StackAsLinkedList()
Stack.test(stack2)
return 0
