@Override
  public boolean containsValue(Object value) {
    if (k1 != null) {
      if (Objects.equals(v1, value)) return true;
      if (k2 != null) {
        if (Objects.equals(v2, value)) return true;
        if (k3 != null) {
          if (Objects.equals(v3, value)) return true;
        }
      }
    }
    for (int i = 0; i < data.length; i += 2) {
      if (data[i] != null && Objects.equals(data[i + 1], value)) return true;
    }
    return false;
  }
@Override
  public boolean containsValue(Object value)