error CS8025: Parsing error

Hello guys, I'm new to coding, however I created a simple 2D game for android devices with the help of a template and some tutorials to modify it. Anyway, I would like to monetize the game with Chartboost ads. I tried to write a script that when the game opens, when the Menu appears the ad will pop up/show. Below you can see the script I made in C#. I am getting this error: Assets/Ad Networks Prefabs/Show Ads.cs(28,9): error CS8025: Parsing error

 using UnityEngine;
 using System.Collections;
 
 public class ShowAds : MonoBehaviour {
 
     string chartboostAppID = "hidden for secure purposes";
     string chartboostAppSignature = "hidden for secure purposes";
 
     // Use this for initialization
     void Start () {
         ChartboostAndroid.init( chartboostAppID, chartboostAppSignature, true );
         ChartboostAndroid.cacheInterstitial( null );
 
         i=Random.Range(1,4);
 
         if(i==2)
         {
             Ads();
         }
         
     }
     
     void  Ads (){
         ChartboostAndroid.showInterstitial( null );
     }
 }
     
     }
     
     // Update is called once per frame
     void Update () {
     
     }
 }