The Quiet Annexe
Ten floors, one lift, nobody in a hurry. Everything you do wrong is visible.
- Floors
- 10
- Lifts
- 1
- People
- ~64
- Arrivals
- 0.14/s average
- Runs for
- 10 min
- Quiet at the end
- 2.5 min
Challenge set v1 · specification
Six buildings
Your submission runs against every one of these on three seeds nobody has seen, and the six scores are averaged. The workbench gives you the same buildings on different seeds, so you can tune against the shape of a problem without tuning against the answer.
Morning Rush
Everyone arrives at once and they all want a different floor.
- Floors
- 20
- Lifts
- 4
- People
- ~312
- Arrivals
- 0.42/s average
- Runs for
- 15 min
- Quiet at the end
- 2.5 min
Home Time
Twenty floors of people who have all decided, simultaneously, to leave.
- Floors
- 20
- Lifts
- 4
- People
- ~330
- Arrivals
- 0.44/s average
- Runs for
- 15 min
- Quiet at the end
- 2.5 min
Lunch
Traffic in both directions at once, and a meeting that runs over.
- Floors
- 15
- Lifts
- 3
- People
- ~393
- Arrivals
- 0.37/s average
- Runs for
- 20 min
- Quiet at the end
- 2.5 min
The Tower
Forty floors. Six lifts. Every journey is long and every mistake is longer.
- Floors
- 40
- Lifts
- 6
- People
- ~699
- Arrivals
- 0.67/s average
- Runs for
- 20 min
- Quiet at the end
- 2.5 min
Bad Monday
Morning peak, three lifts, and one of them fails five minutes in.
- Floors
- 20
- Lifts
- 3
- People
- ~179
- Arrivals
- 0.24/s average
- Runs for
- 15 min
- Quiet at the end
- 2.5 min
Car 2 withdrawn at 5 min
Constants of the world
The same in every building. Difficulty comes from floors, lifts and traffic — never from a car that holds a different number of people.
- Car capacity
- 8 people
- Top speed
- 2.4 floors/s
- Acceleration
- 1.2 floors/s²
- Doors open
- 0.8 s
- Minimum dwell
- 2.0 s
- Doors close
- 0.8 s
- In or out
- 0.6 s per person
- Decisions
- 10 per second
How a run is scored
Half the marks are for getting somebody moving inside thirty seconds, which is roughly when a person starts staring at the indicator. Most of the rest is for nobody being abandoned. The last fifth is journey time, so you cannot win by collecting everybody promptly and then taking them on a tour.
score = 100 × (0.50 × under30s + 0.30 × under90s + 0.20 × flow) flow = clamp(1 − p95(journey) / reference, 0, 1)
Waiting time is every second spent outside a car between your first button press and arriving. Anyone still standing there when the clock stops is counted at the full length of the run — leaving people behind has to be the worst thing you can do, not the cheapest.
Open the workbench