08 双端队列
class Deque(object):
"""双端队列"""
def __init__(self):
self._list = []
def is_empty(self):
"""判断一个队列是否为空"""
return self._list == []
def size(self):
"""返回队列的大小"""
return len(self._list)
def add_ront(self, item):
"""往队列头部添加一个item元素"""
self._list.insert(0, item)
def add_rear(self, item):
"""往队列尾部添加一个item元素"""
self._list.append(item)
def remove_front(self):
"""从队列头部删除一个元素"""
return self._list.pop(0)
def remove_rear(self):
"""从队列尾部删除一个元素"""
return self._list.pop()
if __name__ == '__main__':
q = Deque()
q.enqueue(1)
q.enqueue(2)
q.enqueue(3)
q.enqueue(4)
print(q.dequeue())
print(q.dequeue())
print(q.dequeue())
print(q.dequeue())