实现单向链表的插入与删除代码

在许多编程语言中，如Python、C++或者Java，单向链表是一种常见的数据结构，它的节点包含数据和指向下一个节点的指针。以下是使用Python编写的基本单向链表插入和删除操作的例子：

# 定义链表节点类
class Node:
    def __init__(self, data=None):
        self.data = data
        self.next = None

# 插入新节点到链表头部
def insert_at_head(head, data):
    new_node = Node(data)
    new_node.next = head
    return new_node

# 插入新节点到链表尾部
def insert_at_tail(head, data):
    if not head:
        return Node(data)
    
    current = head
    while current.next:
        current = current.next
    current.next = Node(data)
    return head

# 删除指定值的节点
def delete_node(head, value):
    if not head or not head.data == value:
        return head
    
    if head.data == value:
        head = head.next
        return head
    
    current = head
    while current.next and current.next.data != value:
        current = current.next
        
    if current.next:
        current.next = current.next.next
    return head