class Person
{
    public Person( String n, int a )
    {
        if( a < 0 )
            throw new IllegalArgumentException( );
        
        name = n;
        age = a;
    }
    
    public String getName( )
    {
        return name;
    }
    
    public int getAge( )
    {
        return age;
    }
    
    public String toString( )
    {
        return getName( ) + " " + getAge( );
    }
    
    private String name;
    private int age;
}

class UniversityPerson extends Person
{
    public UniversityPerson( String n, int a, String d )
    {
        super( n, a );
        dept = d;
    }
    
    public String getDept( )
    {
        return dept;
    }
    
    public String toString( )
    {
        return super.toString( ) + " " + getDept( );
    }
    
    private String dept;
}

class Student extends UniversityPerson
{
    public Student( String n, int a, String d, double g )
    {
        super( n, a, d );
        gpa = g;
    }
     
    public double getGPA( )
    {
        return gpa;
    }
    
    
    public String toString( )
    {
        return super.toString( ) + " " + getGPA( );
    }
    
    private double gpa;
}

class Faculty extends UniversityPerson
{
    public Faculty( String n, int a, String d, String r )
    {
        super( n, a, d );
        rank = r;
    }
    
    public String getName( )
    {
        return rank + " " + super.getName( );
    }

    public String getRank( )
    {
        return rank;
    }
    
    
    public String toString( )
    {
        return super.toString( ) + " " + getRank( );
    }
    
    private String rank;
}

public class Day3
{
    // arr.length > 0
    public static Person getYoungest( Person [ ] arr )
    {
        int minIndex = 0;
        
        for( int i = 1; i < arr.length; i++ )
            if( arr[ i ].getAge( ) < arr[ minIndex ].getAge( ) )
                minIndex = i;
        
        return arr[ minIndex ];
    }
    
    public static void main( String [ ] args )
    {
        Person p1 = new Person( "Chris", 37 );
        Person p2 = new Person( "Fran", 42 );
        Student s1 = new Student( "Al", 29,  "SCIS", 3.6 );
        Student s2 = new Student( "JC", 26, "MIS", 3.9 );
        Faculty f1 = new Faculty( "Yi", 40, "SCIS", "DEAN" );
        Faculty f2 = new Faculty( "Ana", 42, "SCIS", "PROFESSOR" );
        
        Person [ ] arr = new Person[ 6 ];
        arr[ 0 ] = p1;
        arr[ 1 ] = p2;
        arr[ 2 ] = s1;
        arr[ 3 ] = f2;
        arr[ 4 ] = f1;
        arr[ 5 ] = s2;
        
        System.out.println( ((UniversityPerson)arr[ 4 ]).getDept( ) );
        
        for( Person p : arr )
            System.out.println( p );
        
        System.out.println( "Youngest person is: " + getYoungest( arr ) );
    }
}