     let shieldCategory : UInt32 = 0x1 << 3
     let lifeBarCategory : UInt32 = 0x1 << 4
     var ammo = 5
-
+    var score = 0
+    
     private var mainLayer : SKNode?
     private var menuLayer : SKNode?
     private var cannon : SKSpriteNode?
     private var ammoDisplay : SKSpriteNode?
+    private var scoreLabel : SKLabelNode?
     //private var explosion : SKEmitterNode?
     private var didShoot = false
     


        self.cannon = self.childNode(withName: "cannon") as? SKSpriteNode
        self.ammoDisplay = self.childNode(withName: "ammoDisplay") as? SKSpriteNode
        self.mainLayer = self.childNode(withName: "mainLayer")
        self.menuLayer = self.childNode(withName: "menuLayer")
        

        mainLayer?.removeAllChildren()
        
        ammo = 5
        score = 0
        
        // Add shields
        for i in 0...6 {
