Python实现无序列表

无序列表
无序列表由一个节点集合组成，每个节点采用显式引用链接到下一个节点。
无序列表操作

unorderedList()
add()
remove()
search()
isEmpty()
size()
append()
index(item)
insert(pos, item)
pop()
pop(pos)
无序列表实现
# python实现无序列表

# Node 类
class Node():
    def __init__(self, element):
        self.data = element
        self.next = None

    def getData(self):
        return self.data

    def getNext(self):
        return self.next

    def setData(self, newelement):
        self.data = newelement

    def setNext(self, newnext):
        self.next = newnext

# 无序列表类
class unorderedList():
    # unorderedList要保持对列表头一个节点的引用
    def __init__(self):
        self.head = None
    # 判断无序列是否为空，即列表头是否指向None
    def isEmpty(self):
        return self.head == None
    # 添加add()方法
    def add(self, item):
        newNode = Node(item)
        newNode.setNext(self.head)
        self.head = newNode

    # 添加size()方法，此过程需要遍历无序列表
    def size(self):
        current = self.head
        count = 0
        while current != None:
            count += 1
            current = current.getNext()
        return count

    # 添加search方法
    def search(self, item):
        current = self.head
        found = False
        while current != None and not found:
            if current.getData() == item:
                found = True
            else:
                current = current.getNext()
        return found

    # 添加remove()方法
    def remove(self, item):
        if not self.search(item):
            return "The unorderedList don't contain this item!"
        previous = None
        current = self.head
        found = False
        while not found:
            if current.getData() == item:
                found = True
            else:
                previous = current
                current = current.getNext()
        # 要删除的节点为第一个节点
        if previous == None:
            self.head = current.getNext()
        else:
            previous.setNext(current.getNext())

    # 添加append()方法
    def append(self, item):
        newNode = Node(item)
        if self.head == None:
            newNode.setNext(self.head)
            self.head = newNode
        else:
            previous = None
            current = self.head
            while current != None:
                previous = current
                current = current.getNext()
            previous.setNext(newNode)

    # 添加index()方法
    def index(self, item):
        current = self.head
        count = -1
        while current != None:
            count += 1
            if current.getData() == item:
                return count
            current = current.getNext()

    # 添加pop()方法
    def pop(self):
        previous = None
        current = self.head
        while current != None:
            previous = current
            current = current.getNext()
        previous.setNext(None)
        return previous.data

    # 添加insert()方法
    def insert(self, pos, item):
        newNode = Node(item)
        previous = None
        current = self.head
        for i in range(pos):
            previous = current
            current = current.getNext()

        # in case of pos = 0
        if previous == None:
            newNode.setNext(self.head)
            self.head = newNode
        else:
            previous.setNext(newNode)
            newNode.setNext(current)

    # traverse the unorderedList
    def println(self):
        current = self.head
        lists = []
        while current != None:
            lists.append(current.data)
            current = current.getNext()
        print(lists)
文章目录

无序列表操作
