title: Swift 3 my game over code doesn't work correctly
body: <p>If I touch besides of the buttons the game crash down. What can I do? And how? I want to ignore all touches which is besides of the buttons. How can I do that?
  Here is my touchesBegan:</p>
  
  <pre><code>    override func touchesBegan(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
      let touch = touches.first
      if let location = touch?.location(in: self),
          let node = self.nodes(at: location).first {
  
          var player = SKSpriteNode()
  
          if node.name == "BlueButton" {
              player = playerB
              playerB.isHidden = false
  
          } else if node.name == "RedButton" {
              player = playerR
              playerR.isHidden = false
  
          } else if node.name == "YellowButton" {
              player = playerY
              playerY.isHidden = false
  
          } else if node.name == "GreenButton" {
              player = playerG
              playerG.isHidden = false
  
          }
          for sprite in [playerB, playerW, playerR, playerY, playerG] {
              sprite?.removeFromParent()
          }
          player.position = CGPoint(x: 0, y: -60)
          addChild(player)
      }
  
  }
  </code></pre>
  
  <p>Here is my touchesEnded function</p>
  
  <pre><code>override func touchesEnded(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
      addChild(playerW)
      playerB.removeFromParent()
      playerR.removeFromParent()
      playerY.removeFromParent()
      playerG.removeFromParent()
  
  }
  </code></pre>