import java.util.Hashtable;
import java.util.Enumeration;

/** a demo of Hashtables in Java 

    @author P. Conrad
    @version CS56, W11, UCSB
*/

public class GradeDictDemo {

    public static void main(String [] args) {

	Hashtable<String,Double> gradeDict = new Hashtable<String,Double>();

	gradeDict.put("A",4.0);
	gradeDict.put("A-",3.7);
	gradeDict.put("B+",3.3);
	gradeDict.put("B",3.0);
	gradeDict.put("B-",2.7);

	// TODO: fill in the rest--this is enough to get the point across

	System.out.println("Here's how to look up the value of a grade:");
	String grade = "B+";
	System.out.println(" Grade = " + grade + 
			   " Value = " + gradeDict.get(grade));


	// Iterating

	System.out.println("Grade table");


	Enumeration<String> e = gradeDict.keys(); 
	while (e.hasMoreElements())
	    {
		
		String k = e.nextElement() ;
		System.out.println(" grade: " + k + 
				   " value: " + gradeDict.get(k));
		
	    }
	


    }


}