21 cars, 88 passengers, 5 bays. 90 seconds on the clock.
88 waiting
You have 90 seconds, starting at your first tap. A bump costs 3 seconds.
Call the cars to the stop in this order: 5, 21, 1, 3, 20, 19, 2, 18, 4, 13, 6, 7, 8, 12, 17, 16, 10, 9, 11, 14, 15.