import java.util.*;

/**
 * Write a description of class ParseStack here.
 * 
 * @author Nobo Komagata 
 * @version 5/30/03
 */
public class ParseStack extends Stack
{
    /**
     * Check the emptiness of the stack
     * 
     * @param       None
     * @return      Emptiness of the stack 
     */
    public boolean emptyS() {
        return super.empty();
    }
    
    /**
     * Push a Category on to the stack
     * 
     * @param       Category
     * @return      void 
     */
    public void pushS(Category s) {
        super.push(s);
    }
    
    /**
     * Pop the Category from the top of the stack
     * 
     * @param       None
     * @return      Category 
     */
    public Category popS() {
        return (Category) super.pop();
    }
    
    /**
     * Return the Category at the top of the stack (without popping)
     * 
     * @param       None
     * @return      Category 
     */
    public Category peekS() {
        return (Category) super.peek();
    }
    
    /**
     * Return a custom String representation (overwrite)
     *
     * @param       None
     * @return      String
     */
    public String toString()
    {
        String s = super.toString();
        return "(bottom)" + s;
    }
}