from collections import deque
def timeOfBuffering(arrivalRate, packets):
    buffer = deque()
    current = 1
    time = 0

    for i in range(0, len(packets), arrivalRate):
        time += 1

        for j in range(i, min(i + arrivalRate, len(packets))):
            packet = packets[j]
            if packet != current:
                buffer.append(packet)

        if current in buffer:
            buffer.remove(current)
        elif current == packets[i]:
            pass
        else:
            return time

        current += 1

    return -1