Design an elevator system for a multi-story building.

Question

Accepted Answer

Design a low-level elevator system to manage multiple elevators efficiently in a building.

Define Elevator class with attributes like currentFloor, direction, and status.
Implement a Building class to manage multiple elevators and floors.
Use a Queue to handle requests from different floors.
Consider edge cases like simultaneous requests and elevator maintenance.
Example: If an elevator is on floor 3 and a request comes from floor 5, it should move up.

Accepted Answer

was it asked in LLD or HLD

Accepted Answer

Upon scoping further specifications were given such as it’s a 50 stories tall commercial complex. Each floor has 1000 people working. 60% of the people arrive between 9-11 am and leave between 5-7 pm. It takes 1 sec for a person to enter or leave the lift. The lift takes 1 sec to traverse between 2 floors etc.

The case boiled down to designing a methodology to calculate the number of lifts that are needed to serve the building’s needs.

Asked in Fidelity International and 8 others

Design an elevator system for a multi-story building.

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