Unexpectedly found nil while unwrapping an Optional value

/
/
/
/
/
/
/ 
import SpriteKit
import GameplayKit
import CoreMotion
import UIKit
class GameScene: SKScene, SKPhysicsContactDelegate {
   
    let manager = CMMotionManager()
    var player = SKSpriteNode()
    var hole = SKSpriteNode()
    var timer = Timer()
    var timerint = 0
    var time = SKLabelNode()
    var minint = 0
    var min = SKLabelNode()
    var pos = SKNode()
    var screenSize:CGSize!
   
   
   
    override func didMove(to view: SKView) {
       
        self.physicsWorld.contactDelegate = self
       
       
        screenSize = self.frame.size
       
      
        time = self.childNode(withName: "time")as! SKLabelNode // here is where i get the error
        min = self.childNode(withName: "min")as! SKLabelNode
       
       
        time.text = String(timerint)
        min.text = String(minint)
       
       
      
       
      
      
        manager.startAccelerometerUpdates()
        manager.accelerometerUpdateInterval = 0.1
        manager.startAccelerometerUpdates(to: OperationQueue.main){
            (Data, error) in
           
            self.physicsWorld.gravity = CGVector(dx: CGFloat((Data?.acceleration.x)!) * 10, dy: CGFloat((Data?.acceleration.y)!) * 10)
           
        }
        if timerint == 0 && minint == 0 {
            timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(GameScene.time1), userInfo: nil, repeats: true)
        }
       
    }
   
    func didBegin(_ contact: SKPhysicsContact) {
        let bodyA = contact.bodyA
        let bodyB = contact.bodyB
       
        if bodyA.categoryBitMask == 1 && bodyB.categoryBitMask == 2 || bodyA.categoryBitMask == 2 && bodyB.categoryBitMask == 1 {
            let gamescene = GameScene(fileNamed: "endscene")
            self.scene?.view?.presentScene(gamescene)
            gamescene?.size = self.size
            timer.invalidate()
           
           
            }
       
       
        if bodyA.categoryBitMask == 2 && bodyB.categoryBitMask == 3 || bodyA.categoryBitMask == 3 && bodyB.categoryBitMask == 2 {
            let gamescene = GameScene(fileNamed: "GameScene")
            self.scene?.view?.presentScene(gamescene)
            gamescene?.size = self.size
           
        }
    }
   
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
       
    }
   
   
   
    @objc func time1(){
        timerint += 1
        time.text = String(timerint)
       
       
        if timerint == 60 {
           
            timerint = 0
            minint += 1
            min.text = String(minint)
            time.text = String(timerint)
        }
       
       
    }
   
   
   
   
   
    override func update(_ currentTime: TimeInterval) {
       
       
    }
}

please help me

Replies

Where do you create the nodes you search for (by name) in lines 35 and 36? Nodes do not have a name unless you give them one.