Question

Consider the following code segment: ArrayList list = new ArrayList(); list.add("One");

list.add("Two");
list.add("Three");
list.add("Four");
list.add("Five");
list.add("Six");
for (int i= 0; i < list.size(); i++)
{
list.remove(i);
}
System.out.println(list.toString()); What is printed when the code segment is executed?
[]
["Two", "Four]
["Two", "Four", "Six"]
["Four", "Five", "Six"]
["Six"]​

Answer 1

The output of the code segment will be:

["Two", "Four", "Six"]

The reason is that the for loop removes the elements from the list one by one, starting with index 0. On the first iteration of the loop, "One" is removed, causing all the elements to shift down by one index. On the second iteration, "Three" is removed, and so on. However, when the loop reaches index 3, "Four" is removed, causing "Five" to shift down to index 3, but the loop variable i is incremented to 4 on the next iteration. As a result, "Five" is not removed, and the loop terminates when i becomes equal to the size of the list. Therefore, after the loop has finished, the list contains the elements "Two", "Four", and "Six". This is confirmed by the output of the call to list.toString().