The next exercises will focus around simulating a supermarket with multiple customers and multiple queues. In contrast to the lift-course we will not simulate a fixed amount of time. Instead we will simulate until all customers are served.


As with the lift we will take tiny steps and will increase the complexity of the model bit by bit. Our end goal is to have a bunch of customers with different items, which all take different amounts of time to scan, which will be served by multiple cashiers.

To get there we start with only one customer and one cashier. Each item should take the same amount of time. To do that, we keep track of the item count in the Variable CustomerItemCount. When one gets processed we simply need do decrement that value.


Because we don't want a fixed amount of time steps, like we did with the lift, we need a different kind of loop. A while-loop loops as long as its condition is true.

    // looped code here

This is exactly what we need to serve all customers until no one is left or for now until all items are gone.


For now your task will be to implement one cashier and one customer with 5 items. Each item should take the same amount of time for now.