ATM Queue

There are $N$ people waiting in a queue at ATM. The $i^{th}$ person in the queue has a power level equal to $A_i$ ($1 \leq A_i \leq N$). The following process happens every second till the queue is not empty. - The person in front of the queue uses the ATM and then leaves the queue. - After the first step, if the queue is empty, the process stops. Otherwise, for each person from left to right (e