import java.util.*;

class Memento {
    private String state；
    public Memento(String state) {
        this.state = state;
    }
    public String getState() {
        return state;
    }
}
class Originator {
    private String state；
    public void setState(String state) {
        this.state = state;
    }
    public String getState() {
        retum state;
    }
    public Memento saveStateToMemento() {
        Return(1)
    }
    public void getStateFromMemento(Memento Memento) {
        state = (2)
    }
}
class CareTaker {
    public(3) {
        mementoList.add(state);
    }
    public(4) {
        return mementoList get(index);
    }
}
class MementoPatternDemo {
    pubic static void main(String[] args) {
        Originator aniginator = new Originator();
        CareTaker careTaker = new careTaker();
        originator.setState("State #1");
        originator.setState("State #2");
        careTaker.add(5)
        originator.setState("State #3");
        careTaker.add(6)
        originator.setState("State #4");
    }