Unknown class _TtC814ViewController in Interface Builder file.について

/*import UIKit
import MapKit

class MapViewController: UIViewController {

@IBOutlet weak var mapView1: MKMapView!

//座標の配列
let coordinatesArray = [
    ["name":"東京駅",    "lat":35.68124,  "lon": 139.76672],
    ["name":"皇居外苑",   "lat":35.68026,  "lon": 139.75801],
    ["name":"国立劇場",   "lat":35.6818,   "lon": 139.74326],
    ["name":"九段下駅",   "lat":35.69555,  "lon": 139.75074]
]

override func viewDidLoad() {
    super.viewDidLoad()
    self.mapView1.delegate = self
    makeMap()
}

func makeMap(){
    //マップの表示域を設定
    let coordinate = CLLocationCoordinate2DMake(coordinatesArray[0]["lat"] as! CLLocationDegrees, coordinatesArray[0]["lon"] as! CLLocationDegrees)
    let span = MKCoordinateSpan(latitudeDelta: 0.05, longitudeDelta: 0.05)
    let region = MKCoordinateRegion(center: coordinate, span: span)
    self.mapView1.setRegion(region, animated: true)
    
    
    var routeCoordinates: [CLLocationCoordinate2D] = []
    for i in 0..<coordinatesArray.count {
        let annotation = MKPointAnnotation()
        let annotationCoordinate = CLLocationCoordinate2DMake(coordinatesArray[i]["lat"] as! CLLocationDegrees, coordinatesArray[i]["lon"] as! CLLocationDegrees)
        annotation.title = coordinatesArray[i]["name"] as? String //ピンの吹き出しに名前が出るように
        annotation.coordinate = annotationCoordinate
        routeCoordinates.append(annotationCoordinate)
        self.mapView1.addAnnotation(annotation)
    }
    var myRoute: MKRoute!
    let directionsRequest = MKDirections.Request()
    var placemarks = [MKMapItem]()
    //routeCoordinatesの配列からMKMapItemの配列にに変換
    for item in routeCoordinates{
        let placemark = MKPlacemark(coordinate: item, addressDictionary: nil)
        placemarks.append(MKMapItem(placemark: placemark))
    }
    directionsRequest.transportType = .walking //移動手段は徒歩
    for (k, item) in placemarks.enumerated(){
        if k < (placemarks.count - 1){
            directionsRequest.source = item //スタート地点
            directionsRequest.destination = placemarks[k + 1] //目標地点
            let direction = MKDirections(request: directionsRequest)
            direction.calculate(completionHandler: {(response, error) in
                if error == nil {
                    myRoute = response?.routes[0]
                    self.mapView1.addOverlay(myRoute.polyline, level: .aboveRoads) //mapViewに絵画
                }
            })
        }
    }
    //ルートがマップに収まるように
    if let firstOverlay = self.mapView1.overlays.first{
        let rect = self.mapView1.overlays.reduce(firstOverlay.boundingMapRect, {$0.union($1.boundingMapRect)})
        self.mapView1.setVisibleMapRect(rect, edgePadding: UIEdgeInsets(top: 35, left: 35, bottom: 35, right: 35), animated: true)
    }
}

}

extension MapViewController:MKMapViewDelegate {

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation {
        return nil
    }
    let reuseId = "pin"
    var pinView = mapView.dequeueReusableAnnotationView(withIdentifier: reuseId)
    if pinView == nil {
        pinView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
        pinView?.canShowCallout = true //吹き出しで情報を表示出来るように
    }else{
        pinView?.annotation = annotation
    }
    return pinView
}

//ピンを繋げている線の幅や色を調整
func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
    let route: MKPolyline = overlay as! MKPolyline
    let routeRenderer = MKPolylineRenderer(polyline: route)
    routeRenderer.strokeColor = UIColor(red:1.00, green:0.35, blue:0.30, alpha:1.0)
    routeRenderer.lineWidth = 3.0
    return routeRenderer
}

}*/
調べて見ましたが海外のものばかりでよくわかりませんでした