// This program inputs the gender and returns an
// array of all objects having that gender.

import java.util.Scanner;
import java.io.FileReader;
import java.io.FileNotFoundException;
public class FindGender
{
    public static void main(String[ ] argv) throws FileNotFoundException
    {
        final int SIZE = 20;
        Person[ ] p = new Person[SIZE];
        String theName = ""; 
        char theGender = '\0';
        int theAge = -1;
        Scanner s = new Scanner(new FileReader("persons.txt"));

        // Create Person array from file.
        for(int i = 0; i < p.length && s.hasNextLine( ); i++)
        {
           theName = s.next( );
           theGender = s.next( ).charAt(0); 
           theAge = s.nextInt( );
           p[i] = new Person(theName, theGender, theAge);
        }

        // Print original array p.
        for(int i = 0; i < p.length && p[i] != null; i++)
            System.out.println(p[i]);

        // Input gender.
        Scanner con = new Scanner(System.in);
        System.out.print("Enter gender to find: ");
        char genderToFind = con.next( ).charAt(0);

        // Create new array for output.
        Person[ ] q = new Person[p.length];

        // Put all Person objects of given gender in array q.
        int genderIndex = 0;
        for(int i = 0; i < p.length && p[i] != null; i++)
            if (p[i].getGender( ) == genderToFind)
                q[genderIndex++] = p[i];

        // Print output array q.
        for(int i = 0; i < q.length && q[i] != null; i++)
            System.out.println(q[i]);

    }
}