/* A Person's data include its name, age, and best friend */
public class Person {
  private String name;
  private int age;
  private Person friend;  //best friend
  public static final int LEGALage=18;

 /** Constructor */
 public Person(String name, int age)
 { this.name= name; this.age= age; }

 /** =This Person is an adult */
 public boolean isAdult()
 { return age >= LEGALage; }

 /** =String description of this Person */
 public String toString()
 { return name + " is " + age; }
 
 /** Make a friend with Person p */
 public void makeFriend(Person p) {
   friend= p;
   // or    this.friend= p;
 }

 /** Become a friend of Person p */
 public void beFriendOf(Person p) {
   p.friend= this;
   // or    p.makeFriend(this);
 }

} // class Person