Python怎么实现栈-创新互联
这篇文章将为大家详细讲解有关Python怎么实现栈,小编觉得挺实用的,因此分享给大家做个参考,希望大家阅读完这篇文章后可以有所收获。
创新互联建站是一家以重庆网站建设公司、网页设计、品牌设计、软件运维、营销推广、小程序App开发等移动开发为一体互联网公司。已累计为成都花箱等众行业中小客户提供优质的互联网建站和软件开发服务。前言使用Python 实现栈。
两种实现方式:
基于数组 - 数组同时基于链表实现
基于单链表 - 单链表的节点时一个实例化的node 对象
完整代码可见GitHub:
https://github.com/GYT0313/Python-DataStructure/tree/master/5-stack
目录结构:
注:一个完整的代码并不是使用一个py文件,而使用了多个文件通过继承方式实现。
arraycollection.py
""" File: abstractcollection.py Author: Ken Lambert """ class AbstractCollection(object): """An abstract collection implementation.""" # Constructor def __init__(self, sourceCollection = None): """Sets the initial state of self, which includes the contents of sourceCollection, if it's present.""" self._size = 0 if sourceCollection: for item in sourceCollection: self.add(item) # Accessor methods def isEmpty(self): """Returns True if len(self) == 0, or False otherwise.""" return len(self) == 0 def __len__(self): """Returns the number of items in self.""" return self._size def __str__(self): """Returns the string representation of self.""" return "[" + ", ".join(map(str, self)) + "]" def __add__(self, other): """Returns a new bag containing the contents of self and other.""" result = type(self)(self) for item in other: result.add(item) return result def __eq__(self, other): """Returns True if self equals other, or False otherwise.""" if self is other: return True if type(self) != type(other) or \ len(self) != len(other): return False otherIter = iter(other) for item in self: if item != next(otherIter): return False return True
abstractstack.py
""" File: abstractstack.py Author: Ken Lambert """ from abstractcollection import AbstractCollection class AbstractStack(AbstractCollection): """An abstract stack implementation.""" # Constructor def __init__(self, sourceCollection = None): """Sets the initial state of self, which includes the contents of sourceCollection, if it's present.""" AbstractCollection.__init__(self, sourceCollection) # Mutator methods def add(self, item): """Adds item to self.""" self.push(item)2. 基于数组
运行示例:
代码:
栈实现:arraystack.py
""" File: abstractstack.py Author: Ken Lambert """ from abstractcollection import AbstractCollection class AbstractStack(AbstractCollection): """An abstract stack implementation.""" # Constructor def __init__(self, sourceCollection = None): """Sets the initial state of self, which includes the contents of sourceCollection, if it's present.""" AbstractCollection.__init__(self, sourceCollection) # Mutator methods def add(self, item): """Adds item to self.""" self.push(item)
数组实现:arrays.py
""" File: arrays.py An Array is a restricted list whose clients can use only [], len, iter, and str. To instantiate, use3. 基于链表= array( , ) The fill value is None by default. """ class Array(object): """Represents an array.""" def __init__(self, capacity, fillValue = None): """Capacity is the static size of the array. fillValue is placed at each position.""" self._items = list() for count in range(capacity): self._items.append(fillValue) def __len__(self): """-> The capacity of the array.""" return len(self._items) def __str__(self): """-> The string representation of the array.""" return str(self._items) def __iter__(self): """Supports iteration over a view of an array.""" return iter(self._items) def __getitem__(self, index): """Subscript operator for access at index.""" return self._items[index] def __setitem__(self, index, newItem): """Subscript operator for replacement at index.""" self._items[index] = newItem
运行示例:
代码:
linkedstack.py
""" linkedstack.py """ from node import Node from abstractstack import AbstractStack class LinkedStack(AbstractStack): """基于单链表实现栈-链表头部为栈顶""" def __init__(self, source_collection=None): self._items = None AbstractStack.__init__(self, source_collection) def __iter__(self): """迭代-使用一个列表实现, 列表第一项为单链表的最后一项""" def visit_nodes(node): if node != None: visit_nodes(node.next) temp_list.append(node.data) temp_list = [] visit_nodes(self._items) return iter(temp_list) def peek(self): """返回栈顶元素""" self._prior_condition() return self._items.data def clear(self): """清空列表""" self._size = 0 self._items = None def push(self, item): """入栈""" self._items = Node(item, self._items) self._size += 1 def pop(self): """出栈""" self._prior_condition() old_item = self._items.data self._items = self._items.next self._size -= 1 return old_item def _prior_condition(self): if self._size == 0: raise KeyError("The stack is empty.")
node.py
""" 链表结构的节点类 """ class Node(object): def __init__(self, data, next=None): self.data = data self.next = next
关于“Python怎么实现栈”这篇文章就分享到这里了,希望以上内容可以对大家有一定的帮助,使各位可以学到更多知识,如果觉得文章不错,请把它分享出去让更多的人看到。
文章名称:Python怎么实现栈-创新互联
网页URL:http://azwzsj.com/article/dgedoc.html