import java.util.Iterator;

public class ResizingArrayStack<Item> implements Iterable<Item>

{

    private Item[] a=(Item[]) new Object[1];

    private int N=0;

    public boolean isEmpty(){return N==0;}

    public int size(){return N;}

    private void resize(int max)

    {

        Item[] temp=(Item[]) new Object[max];

        for(int i=0;i<N;i++)

            temp[i]=a[i];

        a=temp;

    }//end resize

    public void push(Item item)

    {

        if(N==a.length) resize(2*a.length);

            a[N++]=item;

    }//end push

    public Item pop()

    {

        Item item=a[--N];

        a[N]=null;

        if(N>0 && N==a.length/4) resize(a.length/2);

        return item;

    }//end pop

    public Iterator<Item> iterator()

    {return new ReverseArrayIterator();}

   

    private class ReverseArrayIterator implements Iterator<Item>

    {

        private int i=N;

        public boolean hasNext(){return i>0;}

        public Item next(){return a[--i];}

        public void remove(){}

     }

   

    public static void main(String[] args)

    {

        ResizingArrayStack<String> s;

        s=new ResizingArrayStack();

        while(!StdIn.isEmpty())

        {

            String item=StdIn.readString();

            if(!item.equals("-"))

                s.push(item);

         }//end while

        for(String i:s)

            StdOut.printf(i+" ");

    }

}