[数据结构][Python]实现单链表操作（增删改）

淩亂°似流年 2022-01-23 05:51 199阅读 0赞

class Node(object):
        def __init__(self, val, p=0):
            self.data = val
            self.next = p
    
    class LinkList(object):
        def __init__(self):
            self.head = 0
    
        def __getitem__(self, item):
            if self.is_empty():
                print("linklist is empty")
                return
            elif item < 0 or item > self.getlength():
                print("the given item is error")
                return
            else:
                return self.getitem(item)
    
        def __setitem__(self, key, value):
            if self.is_empty():
                print("linklist is empty")
                return
            elif key < 0 or key > self.getlength():
                print("the given item is error")
                return
            else:
                self.delete(key)
                return self.insert(key)
    
        def initlist(self, data):
            self.head = Node(data[0])
            p = self.head
            for i in data[1:]:
                node = Node(i)
                p.next = node
                p = p.next
    
        def getlength(self):
            p = self.head
            length = 0
            while p != 0:
                length += 1
                p = p.next
            return length
    
        def is_empty(self):
            if self.getlength() == 0:
                return True
            else:
                return False
    
        def clear(self):
            self.head = 0
    
        def append(self, item):
            q = Node(item)
            if self.head == 0:
                self.head = q
            else:
                p = self.head
                while p.next != 0:
                    p = p.next
                p.next = q
    
        def getitem(self, index):
            if self.is_empty():
                print('Linklist is empty.')
                return
            j = 0
            p = self.head
            while p.next != 0 and j < index:
                p = p.next
                j += 1
            if j == index:
                return p.data
            else:
                print("target is not exist")
    
        def insert(self, index, item):
            if self.is_empty() or index < 0 or index > self.getlength():
                print('Linklist is empty.')
                return
            if index == 0:
                q = Node(item, self.head)
                self.head = q
            p = self.head
            post = self.head
            j = 0
            while p.next != 0 and j < index:
                post = p
                p = p.next
                j += 1
            if j == index:
                q = Node(item, p)
                post.next = q
                q.next = p
    
        def delete(self, index, item):
            if self.is_empty():
                print('Linklist is empty.')
                return
            if index == 0:
                q = Node(item, self.head)
                self.head = q
            p = self.head
            post = self.head
            j = 0
            while p.next != 0 and j < index:
                post = p
                p = p.next
                j += 1
    
            if index == j:
                post.next = p.next
    
        def index(self, value):
    
            if self.is_empty():
                print('Linklist is empty.')
                return
    
            p = self.head
            i = 0
            while p.next != 0 and not p.data == value:
                p = p.next
                i += 1
    
            if p.data == value:
                return i
            else:
                return -1
    l = LinkList()
    l.initlist([1,2,3,4,5,6])
    print(l.getitem(4))
    l.append(7)
    print(l.getitem(6))
    l.insert(4,10)
    print(l.getitem(4))
    print(l.index(5))
    
    5
    7
    10
    5