python利用头插法单向循环链表

以下是Python代码示例，实现了头插法单向循环链表：

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None
        
class LinkedList:
    def __init__(self):
        self.head = None
        
    def add_to_front(self, data):
        new_node = Node(data)
        if self.head is None:
            self.head = new_node
            new_node.next = self.head
        else:
            curr_node = self.head
            while curr_node.next != self.head:
                curr_node = curr_node.next
            curr_node.next = new_node
            new_node.next = self.head
            self.head = new_node
            
    def print_list(self):
        if self.head is None:
            print("List is empty")
        else:
            curr_node = self.head
            while True:
                print(curr_node.data, end=" ")
                curr_node = curr_node.next
                if curr_node == self.head:
                    break
            print()

使用示例：

ll = LinkedList()
ll.add_to_front(3)
ll.add_to_front(2)
ll.add_to_front(1)
ll.print_list()  # 1 2 3