def dequeue(self):
if self.is_empty():
raise EmptyError("Queue is empty.")
e = self._head._element
self._size -= 1
self._head = self._head._next
if self.is_empty():
self._tail == None
return e
def dequeue(self):
if self.is_empty():
raise EmptyError("Circular queue is empty.")
e = self._tail._next._element
if self._size == 1:
self._tail = None
else:
self._tail._next = self._tail._next._next
self._size -= 1
return e
def __init__(self, arr, merger):
if not arr: raise EmptyError('arr should not empty')
self._data = list(arr)
self._merger = merger
self._tree = [None] * (len(arr) * 4)
self._build_tree(0, 0, self.size - 1)
def front(self):
if self.is_empty():
raise EmptyError('{} is empty'.format(type(self).__name__))
return self._data[self._front]
def dequeue(self):
if self.is_empty():
raise EmptyError('{} is empty'.format(type(self).__name__))
return self._dequeue()
def last(self):
if self.is_empty():
raise EmptyError("Dequeue is empty.")
return self._trailer._prev._element
def first(self):
if self.is_empty():
raise EmptyError("Dequeue is empty.")
return self._header._next._element
def remove_first(self):
if self.is_empty():
raise EmptyError("PositionalList is empty")
return super()._delete_node(self._header._next)
def pop(self):
if self.is_empty():
raise EmptyError('Stack is empty')
return self._data.pop().val
def peek(self):
if self.is_empty():
raise EmptyError("Queue is empty.")
return self._head._element
def max(self):
if self.size > 0:
return self._data[0]
raise EmptyError('Can not get max when heap is empty')
def tail(self):
if self.is_empty():
raise EmptyError('{} is empty'.format(type(self).__name__))
return self._get_tail()
def max_distance(self):
if self.root is None:
raise EmptyError('empty tree has no distance')
return self._depths(self.root.left) + self._depths(self.root.right)
def top(self):
if self.is_empty():
raise EmptyError('Stack is empty')
return self._data[-1]
def remove_first(self):
if self.is_empty():
raise EmptyError("Dequeue is empty.")
return self._delete_node(self._header._next)
def peek(self):
if self.is_empty():
raise EmptyError("Circular queue is empty.")
return self._tail._next._element
def remove_last(self):
if self.is_empty():
raise EmptyError("Dequeue is empty.")
return self._delete_node(self._trailer._prev)
def top(self):
if self.is_empty():
raise EmptyError("Stack is empty.")
return self._head._element
def remove_last(self):
if self.is_empty():
raise EmptyError("PositionalList is empty")
return super()._delete_node(self._trailer._prev)