Day20.java

import java.util.NoSuchElementException;
import java.util.Stack;

public class Day20 {
    private Stack<Integer> stack1 = new Stack<>();
    private Stack<Integer> stack2 = new Stack<>();
    public void enqueue(int item) {
        while (!stack1.isEmpty()) {
            stack2.push(stack1.pop());
        }

        stack1.push(item);

        while (!stack2.isEmpty()) {
            stack1.push(stack2.pop());
        }
    }

    public int dequeue() {
        if (isEmpty()) {
            throw new NoSuchElementException("Queue is empty");
        }

        // Pop the front element from stack1
        return stack1.pop();
    }

    public boolean isEmpty() {
        return stack1.isEmpty();
    }

    public static void main(String[] args) {
        Day20 queue = new Day20();
        queue.enqueue(1);
        queue.enqueue(2);
        queue.enqueue(3);

        System.out.println("Dequeue: " + queue.dequeue());
        System.out.println("Dequeue: " + queue.dequeue());
    }
}