dcapwell commented on code in PR #207: URL: https://github.com/apache/cassandra-accord/pull/207#discussion_r2191090639
########## accord-core/src/main/java/accord/utils/SortedArrays.java: ########## @@ -1793,4 +1794,29 @@ private static void swap(int[] values, int i, int j) values[i] = values[j]; values[j] = t; } + + public static <T extends Comparable<? super T>> BitSet toBitSet(SortedArrays.SortedArrayList<T> src, + SortedArrays.SortedArrayList<T> subset) + { + BitSet bitSet = new BitSet(src.size()); + for (int i = 0; i < src.size(); i++) + { + if (subset.contains(src.get(i))) Review Comment: > we should use foldlIntersection for O(n) versus O(n.lg(n)) complexity Can you explain where this `lg(n)` is coming from? ```java for (int i = 0; i < superset.size(); i++) ``` We are looping, so `O(N)` on that We then call `accord.utils.SimpleBitSet#get` ```java int index = indexOf(i); long bit = bit(i); return 0 != (bits[index] & bit); ``` which should be `O(1)` We then call ```java builder.add(superset.get(i)); ``` `add` is `O(1)` and `get` is also `O(1)` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org For additional commands, e-mail: pr-h...@cassandra.apache.org