Question

这个问题是一个黑客挑战。链接到这里：https://www.hackerrank.com/challenges/insert-a-node-at-a-specific-position-in-a-linked-list

"""
Insert Node at a specific position in a linked list
head input could be None as well for empty list
Node is defined as

 class Node(object):

   def __init__(self, data=None, next_node=None):
       self.data = data
       self.next = next_node

 return back the head of the linked list in the below method. 
"""
#This is a "method-only" submission.
#You only need to complete this method.
def InsertNth(head, data, position):
    node = head 
    if position == 0: 
        node = Node(data)
        node.data = data 
        node.next = head 
        return node
    else: 
        while position > 0: 
            node = node.next 

            i = node.next
            node.next = Node(data)
            node.next.next = i 
            return head

我当前的输出是321024，但我需要它是310542.非常感谢任何帮助！

Answer 1

def InsertNth(head, data, position):
    start = head
    if position == 0:
        return Node(data, head)
    while position > 1:
        head = head.next
        position -= 1
    head.next = Node(data, head.next)
    return start

我没有测试它，但这样的事情应该是正确的。您首先要将引用的副本保存到列表的开头。然后，您应该检查是否将其添加到列表的前面，在这种情况下，您应该返回具有适当值的新起始节点。否则，您循环浏览列表，直到到达所需的位置，此时您将下一个节点设置为具有正确的值和剩余列表。

Answer 2

我们有两种可能的选择。

如果数据应该添加在第一个（位置= 0）然后我们应该将头指针更改为当前节点或
位置应该添加在第 k 个位置，我们使用 head.next 和 position-1 递归更新列表

def insertNodeAtPosition(self, head, data, position):
    if (position == 0) | (head==None):
        return SinglyLinkedListNode(data, head)
    else:
        head.next = self.insertNodeAtPosition(head.next, data, position-1)
        return head

Answer 3

 def InsertNth(head, data, position):
        node = head
        i = 0
        temp = Node(data)
        while node is not None:
            if i == at:
                temp.nextnode = node.nextnode
                node.nextnode = temp
                break
            i += 1
            node = node.nextnode

Answer 4

def insert(self, data, position):
    counter = 1
    current = self.head
    if position > 1:
        while current and counter < position:
            if counter == position - 1:
                data.next = current.next
                current.next = data
                current = current.next
                counter += 1
    elif position == 1:
        data.next = self.head
        self.head = new_element

Answer 5

def insertNodeAtPosition(head, data, position):
    prev_node = head
    if position == 0:
        new_node = SinglyLinkedListNode(data)
        new_node.next = head
        return new_node

    while prev_node is not None:
        new_node = SinglyLinkedListNode(data)

        for _ in range(position-1):
            prev_node = prev_node.next

        new_node.next = prev_node.next
        prev_node.next = new_node
        return head

Answer 6

class SinglyLinkedListNode:
    def __init__(self, node_data):
        self.data = node_data
        self.next = None

class SinglyLinkedList:
    def __init__(self):
        self.head = None
        self.tail = None

def insertNodeAtPosition(head, data, position):
    pos = 0
    current_head = head
    previous_head = head
    while pos <= position:
        if pos == position:
            new_head = SinglyLinkedListNode(data)
            previous_head.next = new_head
            new_head.next = current_head
            return head
        else:
            pos += 1
            previous_head = current_head
            current_head = current_head.next
    return head

Answer 7

def insertNodeAtPosition(head, data, position):
    currNode = head
    while position > 1:
        position -= 1
        currNode = currNode.next

    temp = currNode
    node = SinglyLinkedListNode(data)
    node.next = temp.next
    currNode.next = node
    return head

Answer 8

def insertNodeAtPosition(head, data, position):
    positer = 0
    temp = head
    while temp:
        if positer == position-1:
            newNode = SinglyLinkedListNode(data)
            newNode.next = temp.next
            temp.next = newNode
            break
        else:
            positer+=1
            temp = temp.next
    return head

Answer 9

def insert_after(self, data, pos):
    new_node = Node(data)
    prev = self.head
    pos = pos - 1
    if pos == 0:
        self.insert_front(data)
        return
    while pos > 1:
        prev = prev.next
        pos -= 1
    new_node.next = prev.next
    prev.next = new_node

在特定位置python插入节点

9 个答案: