var timer = Timer()
var time = 210

func decreasetimer() {
    if time > 0 {
    time -= 1
    timerlabel.text = String(time)
  * }else{
    timerlabel.text = String(time)

}

}
@IBOutlet var timerlabel: UILabel!

@IBAction func timerstarter(_ sender: AnyObject) {

    timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(ViewController.processtimer), userInfo: nil, repeats: true)