// Q1
import java.util.Stack;

public class Stacxercise {
	
	public static int sum(Stack<Integer> stackInt) { return -1; }
	
	public static void insert(Stack<Integer> stackInt, int val) {}
	
	public static void sort(Stack<Integer> stackInt) {}
	
	public static void main(String[] args) {
		Stack<Integer> objUnsorted = new Stack<Integer>();
		objUnsorted.push(10); objUnsorted.push(6); objUnsorted.push(2);
		objUnsorted.push(3); objUnsorted.push(4);
		System.out.println(sum(objUnsorted));
		
		Stack<Integer> objSorted = new Stack<Integer>();
		objSorted.push(1); objSorted.push(3);
		insert(objSorted, 4); insert(objSorted, 2); insert(objSorted, 0);
		System.out.println(objSorted);
		
		sort(objUnsorted);
		System.out.println(objUnsorted); // now sorted =P
	}
}