// Jeremy Lipschutz
// Short program showing how to construct and use maps
import java.util.*;

public class Courses {
   public static void main(String[] args) {
      // course names to their corresponding instructor
      Map<String, String> courses = new TreeMap<String, String>();
      
      // instructors mapping to course names
      
      courses.put("142a", "Omar Ibrahim");
      courses.put("143a", "Jeremy Lipschutz");
      courses.put("143b", "Jeremy Lipschutz");
      courses.put("154a", "Kasey Champion");
      courses.put("163a", "Soham Pardeshi");
      
      System.out.println(courses.get("154a"));
      
      System.out.println(courses.containsKey("143a"));
      System.out.println(courses.size());
      
      //courses.put("143a", "Raymond Berry");
      
      System.out.println(courses.keySet());
      
      
      System.out.println(courses);
      
      for(String course : courses.keySet()) {
         String instructor = courses.get(course);
         System.out.println(instructor + " is teaching " + course);
      }
   }
}