void zamien() throws EmptyStackException{
    Scanner sc = new Scanner(System.in);
    while(sc.hasNext()){
        String[] lol = sc.nextLine().split(" ");
            if(lol[0].equals("end")) break;
        for(int i= 0; i<lol.length; i++)
        push(lol[i]);
    
       while(!isEmpty()){
            System.out.print(pop().toString() + " ");
       }   
       System.out.println();
    }