class Stack(object):
def __init__(self):
self.__list = LinkList()
def push(self, item):
self.__list.push(Node(item))
def pop(self):
return self.__list.pop().item_value
def peek(self): # add exercise 1.3.7
return self.__list[0].item_value
def is_empty(self):
return len(self.__list) == 0
def size(self):
return len(self.__list)
def __iter__(self):
self.__data_list.__iter__()
return self
def __next__(self):
return self.__data_list.__next__()
class Deque(object):
def __init__(self):
self.__link_list = LinkList()
def is_empty(self):
return len(self.__link_list) == 0
def size(self):
return len(self.__link_list)
def push_left(self, item):
self.__link_list.push(Node(item))
def push_right(self, item):
self.__link_list.append(Node(item))
def pop_left(self):
return self.__link_list.pop().item_value
def pop_right(self):
result = self.__link_list[self.size() - 1]
self.__link_list.remove(self.size() - 1)
return result.item_value