function New()
 local queue = {}
 queue._frontIndex = 1
 queue.Size = 0
 return queue
end

function Enqueue(queue, item)
 queue[queue._frontIndex + queue.Size] = item
 queue.Size = queue.Size + 1
end

function Dequeue(queue)
 if (queue.Size == 0) then
  return nil
 end

 local item = queue[queue._frontIndex]
 queue[queue._frontIndex] = nil
 queue._frontIndex = queue._frontIndex + 1
 queue.Size = queue.Size - 1
 return item
end