//  This is an unfinished class of objects representing stacks of 
//  elements of type int.

public class Stack {

    private const int MAX = 1000;  // Maximum height of a stack.
    private int [ ] contents;      // Holds contents of the stack.
    private int ht;                // Holds height of the stack.

    public Stack()
    {
        contents = new int[MAX];
        ht = 0;
    }

    public int height() 
    {
    }

    public int top() 
    {
	if (ht != 0)
	    return contents[ht - 1];
	else 
	    throw new Exception("Stack is empty.");
    }

    public void push(int x) 
    {
	if (ht != MAX) 
        {
	    contents[ht] = x;
	    ht = ht + 1;
	}
	else 
	    throw new Exception("Stack is full.");
    }

    public void pop() 
    {
    }

    public void reset()
    {
    }

    public string contentsToString() 
    {
    }

}