Queue Check-in Simulation with Capacity Limit

Problem There is a single check-in line. You are given an integer array arrivalTimes where arrivalTimes[i] is the time when person i arrives at the end of the line. Rules: Only one person is processed at a time. The person at the front takes 30 seconds to check in. When a person arrives, if the number of people currently waiting/being served in the system is greater than 10, that person leaves immediately and will not check in. Return an array result: If person i is served, result[i] is the time they start service. Otherwise, result[i] = null. Assume arrivalTimes is non-decreasing; ties are enqueued in input order. Input Integer array arrivalTimes Output Array result (each entry is an integer or null) Constraints (suggested) 1 <= len(arrivalTimes) <= 2e5 0 <= arrivalTimes[i] <= 1e9 Examples arrival=[0,0,0] → result=[0,30,60] arrival=[0,10,20] → result=[0,30,60] arrival=[0,100] → result=[0,100] 12 people arrive at time 0 → first 11 served, 12th leaves arrival=[0,15,15,16] → result=[0,30,60,90] Example Input 3 0 0 0 Output 0 30 60