Each flower blooms on the closed range [start, end]: it is in bloom at time t when start <= t <= end. Given flowers and an array people of arrival times, return an array with, for each person, how many flowers are in bloom when they arrive.
- The answer for each person goes at that person's original index
- All arrival times are known up front, and they may repeat or be unsorted
- A flower with
start === end blooms for exactly one moment - Times can be as large as
109; an empty flowers gives zeros, an empty people gives [] - Target: O((n + q) log n), not a scan of all flowers per person