#69 ConcurrentModificationException During Iteration

Companies:

OTP Bank

Themes:

JavaCollections & GenericsCode Review

What will be printed to the screen?

public class Main {
    public static void main(String[] args) {

        List<String> stringList = new ArrayList<>();
        stringList.add("one");
        stringList.add("one and a half");
        stringList.add("two");
        stringList.add("two and a half");
        stringList.add("three and a half");

        System.out.println("Before " + stringList);
        Iterator<String> stringIterator = stringList.iterator();
        while (stringIterator.hasNext()) {
            String next = stringIterator.next();
            if (next.equals("two and a half")) {
                stringList.add("three");
            }
        }

        System.out.println("After " + stringList);
    }
}

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