CS0246 Error: LinkedList could not be found

I am getting this error error CS0246: The type or namespace name LinkedList1’ could not be found. Are you missing a using directive or an assembly reference. I am making continuous road which is moving towards the player. I have searched it but none of the solution work.Please help me thanx.

using UnityEngine;
using System.Collections;


public class MoveScript : MonoBehaviour {

public Transform prefab;
public LinkedList<Transform> roads = new LinkedList<Transform>();
private float posY = 0.0f;
private int numberOfRoads = 3;

void Start()
{
 for(int i=0;i<numberOfRoads>;i++)
{
 Transform road = Instantiate(prefab) as Transform;
road.Translate(0, posY, i* road.localScale.z);
roads.AddLast(road);
}
}

void Update()
{
 Transform firstRoad = roads.First.Value;
 Transform lastRoad  = roads.Last.Value;

 if(firstRoad.localPosition.z < -5f)
{
 roads.Remove(firstRoad);
 Destroy(firstRoad.gameObject);
 
Transform newRoad = Instantiate(prefab, new Vector3(0,posY,lastRoad.localPosition.z + last.Road.localScale.z), Quaternion.identity)as Transform;
roads.AddLast(newRoad);

}

 foreach(Transform road in roads){
 road.Translate(0,0,-8f*Time.deltaTime);
}
}
}

You’re not including the right namespace for a LinkedList.

Add to your using’s at the top:

System.Collections.Generic;