$($c$)$ Given the sequence $6,8,1,7,4,2,5,9,$ perform queue operations from left to right of enque and

deque operations such that the deque operations would produce the output $6,1,8,7,2$ to show

they're being served. Some items will not be served due to certain requirements of the system not

being met. They will leave and join the queue again. For these items, your instructions should show

clearly that they have been removed and join the queue again.

Also show the items still in the queue in the finished queue configuration.

The queue object que is created from the class Queue. You should show the queue configuration or

horizontal container for each operation performed. For example, que.enque$(10)$ and que.deque$()$

means enqueue $10$ into queue and removed from front again. Also, que.enque$($que$.$dequeu$())$

means item had been dequed and enqued again.

$($d$)$ Describe the operational steps to sort the sequence of items in $($c$)$ using the queue operations and

an extra queue. What would be the time complexity of this sorting?