This type Node already define : Shows error in ecllipse

#1

import java.util.Scanner;
class Node
{
int data;
Node next;
Node(int d)
{
data = d;
next = null;
}
}

public class FindMiddle {
Node head;

public static void main(String[] args) {
	// TODO Auto-generated method stub
	Scanner sc = new Scanner(System.in);
	int tc = sc.nextInt();
	while(tc-->0)
	{
		int n = sc.nextInt();
		FindMiddle llist = new FindMiddle();
		int a1 = sc.nextInt();
		Node head = new Node(a1);
		llist.Addtothelast(head);
		for(int i=1 ; i<n ; i++)
		{
			int a = sc.nextInt();
			llist.Addtothelast(new Node(a));
		}
		
		System.out.println(getMiddle(llist.head));
	}

}


static int getMiddle(Node head2) {
	// TODO Auto-generated method stub
	Node slow_ptr = head2;
	Node fast_ptr = head2;
	if(head2!=null)
	{
		while(fast_ptr !=null && fast_ptr.next !=null)
		{
			fast_ptr = fast_ptr.next.next;
			slow_ptr = slow_ptr.next;
		}
		return slow_ptr.data;
	}
	return 0;
}


private void Addtothelast(Node head2) {
	if(head==null)
	{
		head = head2;
	}
	else
	{
		Node temp = head;
		while(temp.next!=null)
		{
			temp=temp.next;
			temp.next = head2;
		}
	}
}

}