MainQueue.java

public class Main {
    public static void main(String[] args) {
        Queue<Integer> qu = new Queue<>();
        qu.Insert(1);
        qu.Insert(2);
        qu.Insert(3);

        print(qu);
        print(clone(qu));
        System.out.println(isIn(qu , 3));
    }
    public static <T> Queue<T> clone(Queue<T> qu) {
        Queue<T> que = new Queue<>();
        Queue<T> que1 = new Queue<>();

        while(!qu.IsEmpty()) {
            que.Insert(qu.Head());
            que1.Insert(qu.Remove());
        }

        while (!que1.IsEmpty()) {
            qu.Insert(que1.Remove());
        }

        return que;
    }

    public static <T> void print(Queue<T> qu) {
        Queue<T> qu1 = new Queue<>();
        System.out.print(qu.Head());
        qu1.Insert(qu.Remove());

        while (!qu.IsEmpty()) {
            System.out.print("," + qu.Head());
            qu1.Insert(qu.Remove());
        }
        while (!qu1.IsEmpty()) {
            qu.Insert(qu1.Remove());
        }
        System.out.println();
    }

    public static boolean isIn(Queue<Integer> qu , int num) {
        Queue<Integer> qu1 = new Queue<>();
        boolean b = false;

        while (!qu.IsEmpty()) {
            if (num == qu.Head())
                b = true;
            qu1.Insert(qu.Remove());
        }
        while (!qu1.IsEmpty()) {
            qu.Insert(qu1.Remove());
        }

        return b;
    }

    
}