public class Solution { public static void main(String[] args) { System.out.println(getInsertTimeInMs(new ArrayList())); System.out.println(getInsertTimeInMs(new LinkedList())); } public static long getInsertTimeInMs(List list) { long startTime = System.currentTimeMillis(); insert10000(list); long timeDifference = System.currentTimeMillis() - startTime; return timeDifference; } public static void insert10000(List list) { for (int i = 0; i < 10000; i++) { list.add(0, new Object()); } } }