Alert Monitor — Rolling Window + Severity Distribution + Spike Detection

Requirements Create a class that stores alerts labeled with both a timestamp and a severity, then supports these three operations: Alert timestamps are supplied in non-decreasing order, and the class does not need to support concurrent access. Examples For a most-recent timestamp of ts = 3720: The distribution is restricted to the hour bucket that begins at timestamp 3600, while the spike result gives the next strictly higher minute count for each listed minute.