*       the integral of our function, between X permits and X-K permits, assuming we want to
   *       spend K saved permits.
   * </ol>
   *
   * <p>In summary, the time it takes to move to the left (spend K permits), is equal to the area of
   * the function of width == K.
   *
   * <p>Assuming we have saturated demand, the time to go from maxPermits to thresholdPermits is