private void Awake()
 {
     if (indexCurrentScene > 1)
     {
         UnityADSInterstitialClass = GameObject.FindWithTag("GameController").GetComponent <UnityADSInterstitial>();
     }
 }
 void Awake()
 {
     spawnEnemiesClass         = GameObject.FindWithTag("GameController").GetComponent <SpawnEnemies> ();
     audioGame                 = GameObject.FindWithTag("GameController").GetComponent <AudioSource> ();
     UnityADSInterstitialClass = GameObject.FindWithTag("GameController").GetComponent <UnityADSInterstitial>();
     fireButtonAnimator        = fireButton.GetComponent <Animator>();
     shellButtonAnimator       = shellButton.GetComponent <Animator>();
     shellButtonImage          = shellButton.GetComponent <Image>();
     missileButtonImage        = missileButton.GetComponent <Image>();
 }