import unit4.collectionsLib.Stack;
public class tar2
{
public static int tar2(Stack <Integer> m,int k)
    {

         int a=0;

        while(!m.isEmpty() && k>=1)
        {
           a=m.pop();
           k--;
        }
          if(k==0)return a;
          else return -1;
        }

    }
////////////
import unit4.collectionsLib.Stack;
public class main
{
public static void main(String []args)
{
 Stack <Integer>m = new Stack<Integer>();
    m.push(1);
    m.push(2);
    m.push(3);
    m.push(4);
    m.push(5);
    m.push(6);
    m.push(7);


    System.out.println(tar2.tar2(m,7));
}
}
///////////////////////////////////////////////////////////
import unit4.collectionsLib.Stack;
public class tar3
{
public static Stack <Integer> tar3(Stack <Integer> a,Stack <Integer> b)
    {

         Stack <Integer> temp=new Stack<Integer>();

        while(!a.isEmpty() && !b.isEmpty())
        {
           if(a.top()>b.top() || a.top()==b.top())temp.push(a.pop());
           if(a.top()==b.top()){temp.push(a.pop());b.pop();}
           else temp.push(b.pop());
        }
          if(!a.isEmpty())
             {
              while(!a.isEmpty())
              temp.push(a.pop());
            }
            if(!b.isEmpty())
            {
              while(!b.isEmpty())
              temp.push(a.pop());
            }
            return temp;
        }

    }
////////
import unit4.collectionsLib.Stack;
public class main2
{
public static void main2(String []args)
{
 Stack <Integer>m = new Stack<Integer>();
  Stack <Integer>d = new Stack<Integer>();
    m.push(1);
    d.push(2);
    m.push(3);
    d.push(3);
    d.push(4);
    d.push(5);
    m.push(6);
    m.push(7);


    System.out.println(tar3.tar3(m,d));
}
}