Here is a question that I got during the amazon onsite interview round.

Amazon is delivering packages to its customers through some delivery trucks in its fullfillment center. The packages are loaded such that the nearest(by distance) packages are delivered first for efficiency purposes. Currently there is only one conveyer belt to load the packages. Now AMZN wants to expand its fulfillment center and add more conveyer belts to increase production. Build the technology for this expansion.