How do unity ads need to be shown in editor?

I have a restart button and a main menu button. When the user clicks(taps) any of the buttons my ads should show up. So, I made a adscript to call a restart script. But it didn't work. Please help. my adscript:

using UnityEngine;

using System.Collections;

using UnityEngine.Advertisements;

public class adscript : MonoBehaviour {

 public restart res;
 
 // Use this for initialization
 void Start () {
     Advertisement.Initialize ("*****");
     
 }
 
 // Update is called once per frame
 void Update () {
 
 }
 public void click()
 {
 

     if (Advertisement.isReady ()) {
         Advertisement.Show ();
         Debug.Log ("adshown");
     } 
     else {
         res.cal ();

     }
     res.cal ();
 }

}