Segregate even and odd nodes in sorted order in swift

Swift program for Segregate even and odd nodes in sorted order. Here problem description and other solutions.

import Foundation
// Swift 4 program for
// Segregate even and odd nodes in ascending order

// Linked list node
class LinkNode
{
	var data: Int;
	var next: LinkNode? ;
	init(_ data: Int)
	{
		self.data = data;
		self.next = nil;
	}
}
class SingleLL
{
	var head: LinkNode? ;
	init()
	{
		self.head = nil;
	}
	// Add new node at the end of linked list
	func insert(_ value: Int)
	{
		// Create a node
		let node: LinkNode? = LinkNode(value);
		if (self.head == nil)
		{
			self.head = node;
		}
		else
		{
			var temp: LinkNode? = self.head;
			// Find last node
			while (temp!.next  != nil)
			{
				// Visit to next node
				temp = temp!.next;
			}
			// Add node at last position
			temp!.next = node;
		}
	}
	// Display all Linked List elements
	func display()
	{
		if (self.head  != nil)
		{
			var temp: LinkNode? = self.head;
			while (temp  != nil)
			{
				// Display node value
				print(" ",temp!.data, terminator: " ");
				// Visit to next node
				temp = temp!.next;
			}
		}
		else
		{
			print("Empty Linked list");
		}
	}
	func sortedAdd(_ element: LinkNode? )
	{
		if (self.head == nil)
		{
			self.head = element;
		}
		else if (self.head!.data >= element!.data)
		{
			element!.next = self.head;
			self.head = element;
		}
		else
		{
			var temp: LinkNode? = self.head;
			// Finding location of inserting node
			while (temp!.next  != nil && 
              temp!.next!.data < element!.data)
			{
				// Visit to next node
				temp = temp!.next;
			}
			// Add node 
			element!.next = temp!.next;
			temp!.next = element;
		}
	}
	func segregateNode(_ odd: SingleLL , _ even : SingleLL )
	{
		var node: LinkNode? = nil;
		// Iterating the linked list node
		while (self.head  != nil)
		{
			node = self.head;
			// Visit to next node
			self.head = node!.next;
			// Set null to next node
			node!.next = nil;
			if (node!.data % 2 == 0)
			{
				// When node value is Even
				even.sortedAdd(node);
			}
			else
			{
				// When node value is Odd
				odd.sortedAdd(node);
			}
		}
	}
	static func main()
	{
		// Create linked lists
		let sll: SingleLL = SingleLL();
		let odd: SingleLL = SingleLL();
		let even: SingleLL = SingleLL();
		// Linked list sll
		// 4 → 3 → 5 → 2 → 11 → 1 → 6 → NULL
		sll.insert(4);
		sll.insert(3);
		sll.insert(5);
		sll.insert(2);
		sll.insert(11);
		sll.insert(1);
		sll.insert(6);
		print("Initial Element");
		// Display all node
		sll.display();
		sll.segregateNode(odd, even);
		print("\nEven Element");
		// Display all even node
		even.display();
		print("\nOdd Element");
		// Display all odd node
		odd.display();
	}
}
SingleLL.main();

Output

Initial Element
  4   3   5   2   11   1   6
Even Element
  2   4   6
Odd Element
  1   3   5   11