// "Replace Stream API chain with loop" "true" import java.util.Arrays; import java.util.List; import java.util.LongSummaryStatistics; public class Main { public static LongSummaryStatistics test(List<List<String>> list) { return list.stream().filter(a -> a != null).flatMap(lst -> lst.stream()).mapToLong(s -> s.length()).summa<caret>ryStatistics(); } public static void main(String[] args) { System.out.println(test(Arrays.asList(null, Arrays.asList("aaa", "b", "cc", "dddd"), Arrays.asList("gggg")))); } }