There is a queue for the self-checkout tills at the supermarket. Your task is write a function to calculate the total time required for all the customers to check out!

the_supermarket_queue.rb

def queue_time(customers, n)
  registers = Array.new(n, 0)
  while !customers.empty?
    idx = registers.index(registers.min)
    registers[idx] += customers.shift unless customers.empty?
  end
  registers.max

# if I had to do it in one line 
# customers.each{|time| registers[registers.index(registers.min)] = (time + registers.min)}


end