You are in a supermarket with only self-checkout counters. Write a function to calculate the total time needed for all the customers to check out.

The function signature is as such:

computeQueueTime(customers, n)

• customers: An array of positive integers. Each integer represents a customer, and its value is how long they require to check out.
• n: The number of self-checkout counters in the supermarket.

Here are some examples:

computeQueueTime([5,3,4], 1)

• should return 12
• because when n=1, the total time is just the sum of the times

computeQueueTime([10,2,3,3], 2)

• should return 10
• because here n=2 and the 2nd, 3rd, and 4th people in the
• queue finish before the 1st person has finished.

computeQueueTime([2,3,10], 2)

• should return 12

You can assume the following:

• There is only a single queue to use the counters.
• The order of the queue will never change.
• The person at the front of the queue proceeds to a counter as soon as it becomes free with no lag time.

Management is thinking to re-introduce some traditional staffed counters to facilitate faster checking out of customers who are less conversant with self-checkout.

These trained staff will be able to serve a customer twice as fast as a self-checkout counter.

Modify your function to incorporate a second type of counter. You should be able to use this function to advice management exactly how much faster the checkouts will be. The new function signature should be:

computeQueueTime(customers, n, m)

• m (new): The number of traditional staffed counters that perform checkouts twice as fast as self-checkout counters.

Note:

• There is still only 1 queue to access all counters, regardless of the type of counter.
• Assume all customers are still the same and are not split by how conversant they are with self-checkout. The first person in the queue continues to use whichever counter is available.

• This was adapted from a kata on Codewars.
• The supermarket queue is analogous to the thread pool in computer science.
• Concept of concurrency in computer science.