Segregate even and odd nodes in sorted order in php

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

<?php
// Php program for
// Segregate even and odd nodes in ascending order

// Linked list node
class LinkNode
{
	public $data;
	public $next;
	public	function __construct($data)
	{
		$this->data = $data;
		$this->next = NULL;
	}
}
class SingleLL
{
	public $head;
	public	function __construct()
	{
		$this->head = NULL;
	}
	// Add new node at the end of linked list
	public	function insert($value)
	{
		// Create  node
		$node = new LinkNode($value);
		if ($this->head == NULL)
		{
			$this->head = $node;
		}
		else
		{
			$temp = $this->head;
			// Find last node
			while ($temp->next != NULL)
			{
				// Visit to next node
				$temp = $temp->next;
			}
			// Add node at last position
			$temp->next = $node;
		}
	}
	// Display all Linked List elements
	public	function display()
	{
		if ($this->head != NULL)
		{
			$temp = $this->head;
			while ($temp != NULL)
			{
				// Display node value
				echo "  ",$temp->data;
				// Visit to next node
				$temp = $temp->next;
			}
		}
		else
		{
			echo "Empty Linked list\n";
		}
	}
	public	function sortedAdd($element)
	{
		if ($this->head == NULL)
		{
			$this->head = $element;
		}
		else if ($this->head->data >= $element->data)
		{
			$element->next = $this->head;
			$this->head = $element;
		}
		else
		{
			$temp = $this->head;
			// Finding location of inserting node
			while ($temp->next != NULL && 
                   $temp->next->data < $element->data)
			{
				// Visit to next node
				$temp = $temp->next;
			}
			// Add node 
			$element->next = $temp->next;
			$temp->next = $element;
		}
	}
	public	function segregateNode($odd, $even)
	{
		$node = NULL;
		// Iterating the linked list node
		while ($this->head != NULL)
		{
			$node = $this->head;
			// Visit to next node
			$this->head = $node->next;
			// Set null to next node
			$node->next = NULL;
			if ($node->data % 2 == 0)
			{
				// When node value is Even
				$even->sortedAdd($node);
			}
			else
			{
				// When node value is Odd
				$odd->sortedAdd($node);
			}
		}
	}
	public static
	function main($args)
	{
		// Create linked lists
		$sll = new SingleLL();
		$odd = new SingleLL();
		$even = new 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);
		echo "Initial Element\n";
		// Display all node
		$sll->display();
		$sll->segregateNode($odd, $even);
		echo "\nEven Element\n";
		// Display all even node
		$even->display();
		echo "\nOdd Element\n";
		// Display all odd node
		$odd->display();
	}
}
SingleLL::main(array());

Output

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