Anticlockwise spiral conversion of doubly linked list in golang

Go program for Anticlockwise spiral conversion of doubly linked list. Here problem description and other solutions.

package main
import "fmt"
// Go program for
// Convert a doubly linked list anticlockwise spiral form

// This is Linked List Node
type LinkNode struct {
	data int
	next * LinkNode
	prev * LinkNode
}
func getLinkNode(data int) * LinkNode {
	// return new LinkNode
	return &LinkNode {
		data,
		nil,
		nil,
	}
}
type DoublyLinkedList struct {
	head * LinkNode
	tail * LinkNode
}
func getDoublyLinkedList() * DoublyLinkedList {
	// return new DoublyLinkedList
	return &DoublyLinkedList {
		nil,
		nil,
	}
}
// Insert new node at end position
func(this *DoublyLinkedList) insert(value int) {
	// Create a node
	var node * LinkNode = getLinkNode(value)
	if this.head == nil {
		// Add first node
		this.head = node
		this.tail = node
		return
	}
	// Add node at last position
	this.tail.next = node
	node.prev = this.tail
	this.tail = node
}
// Display node element of doubly linked list
func(this DoublyLinkedList) display() {
	if this.head == nil {
		fmt.Println("Empty Linked List")
	} else {
		fmt.Print("Linked List Head to Tail :")
		// Get first node of linked list
		var temp * LinkNode = this.head
		// iterate linked list 
		for (temp != nil) {
			// Display node value
			fmt.Print("  ", temp.data)
			// Visit to next node
			temp = temp.next
		}
		fmt.Print("\nLinked List Tail to Head :")
		// Get last node of linked list
		temp = this.tail
		// iterate linked list 
		for (temp != nil) {
			// Display node value
			fmt.Print("  ", temp.data)
			// Visit to prev node
			temp = temp.prev
		}
	}
}
func(this *DoublyLinkedList) spiralTransform() {
	if this.head == nil || this.head.next == nil {
		return
	}
	var last * LinkNode = this.tail
	var current * LinkNode = this.head
	var auxiliary * LinkNode = nil
	var temp * LinkNode = nil
	var back * LinkNode = nil
	// Set new head
	this.head = this.tail
	for (current != nil && last != nil) {
		if current == last {
			current.next = nil
			current.prev = back
			this.tail = current
			// Set new last node
			return
		} else if current.next == last {
			current.next = nil
			current.prev = last
			last.next = current
			last.prev = back
			// Set new last node
			this.tail = current
			return
		}
		// Swap link
		auxiliary = current.next
		temp = last.prev
		current.prev = last
		last.next = current
		current.next = temp
		last.prev = back
		back = current
		current = auxiliary
		last = temp
	}
}
func main() {
	var dll * DoublyLinkedList = getDoublyLinkedList()
	// Insert following linked list nodes
	dll.insert(1)
	dll.insert(2)
	dll.insert(3)
	dll.insert(4)
	dll.insert(5)
	dll.insert(6)
	dll.insert(7)
	dll.insert(8)
	dll.insert(9)
	fmt.Println("\nBefore anticlockwise spiral conversion")
	// Display all node
	dll.display()
	fmt.Println("\nAfter anticlockwise spiral conversion")
	dll.spiralTransform()
	dll.display()
}

Output

Before anticlockwise spiral conversion
Linked List Head to Tail :  1  2  3  4  5  6  7  8  9
Linked List Tail to Head :  9  8  7  6  5  4  3  2  1
After anticlockwise spiral conversion
Linked List Head to Tail :  9  1  8  2  7  3  6  4  5
Linked List Tail to Head :  5  4  6  3  7  2  8  1  9