I just came across skip lists as part of a sliding-window aggregator in Apache Samza's metrics system[0]. So cool! Being able to work with a range of values in

I just came across skip lists as part of a sliding-window aggregator in Apache Samza's metrics system[0]. So cool! Being able to work with a range of values in somewhere between O(1)and O(log n) time, while still providing ordered key/value mappings, is great. Dug through java.util.concurrent looking for more structures, but this seems to be the most interesting of the bunch. [0] https://github.com/apache/samza/blob/master/samza-api/src/main/java/org/apache/samza/metrics/SlidingTimeWindowReservoir.java https://github.com/apache/samza/blob/master/samza-api/src/ma...