Laravel sélectionnez la valeur multiple dans le formulaire Modifier

<select name="cities[]" class="city form-control" data-placeholder="Pilih Kota" style="width: 100%;" multiple="multiple">
                    @foreach($cities as $city)
                        @if(in_array($city->id, $zoneCityIds))
                        <option value="{{ $city->id }}" selected="true">{{ $city->name }}</option>
                        @else
                        <option value="{{ $city->id }}">{{ $city->name }}</option>
                        @endif 
                    @endforeach
                    </select>
samsul aripin