day 24.php

<?php

class Node
{
    public $data;
    public $next;

    function __construct($d)
    {
        $this->data = $d;
        $this->next = null;
    }
}

class Solution
{

    function removeDuplicates($head)
    {
        $currentNode = $head;
        while ($currentNode != null && $currentNode->next != null) {
            $node = $currentNode;
            while ($node->next != null) {
                if ($node->next->data === $currentNode->data) {
                    $next = $node->next->next;
                    $node->next = $next;
                } else {
                    $node = $node->next;
                }
            }
            $currentNode = $currentNode->next;
        }

        return $head;
    }

    function insert($head, $data)
    {
        //complete this method
        $p = new Node($data);
        if ($head == null) {
            $head = $p;
        } else {
            if ($head->next == null) {
                $head->next = $p;
            } else {
                $start = $head;
                while ($start->next != null) {
                    $start = $start->next;
                }
                $start->next = $p;
            }
        }
        return $head;
    }

    function display($head)
    {
        $start = $head;
        while ($start) {
            echo $start->data, ' ';
            $start = $start->next;
        }
    }
}

$T = intval(fgets(STDIN));
$head = null;
$mylist = new Solution();
while ($T-- > 0) {
    $data = intval(fgets(STDIN));
    $head = $mylist->insert($head, $data);
}
$head = $mylist->removeDuplicates($head);
$mylist->display($head);