@Override public boolean equals(Object o) {
            if (this == o)
                return true;
            if (o == null || getClass() != o.getClass())
                return false;

            Node node = (Node) o;

            if (val != node.val)
                return false;
            return copyVal == node.copyVal;
        }
Why Did you create this class? what does it do?
src/problems/medium/TwoKeysKeyboard.java