def new_remote_control_car:
  {
    "battery_percentage": 100,
    "distance_driven_in_meters": 0,
    "nickname": null,
  }
;

def new_remote_control_car(nickname):
  {
    "battery_percentage": 100,
    "distance_driven_in_meters": 0,
    "nickname": nickname,
  }
;

def display_distance: "\(.["distance_driven_in_meters"]) meters";

def display_battery: .["battery_percentage"]| if . != 0 then "Battery at \(.)%" else "Battery empty" end;

def drive:
  if .["battery_percentage"] == 0 then . else
  .|.["battery_percentage"] -= 1|.["distance_driven_in_meters"] += 20
  end;