/*
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package student;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;

/**
 *
 * @author Agata Rybak
 */
public class AppMain {
    private static EntityManager entitymanager;

    public static void main(String[] args) {
        String filePath = "D:/test.txt";

        List<String> param = readFile(filePath);

        String courseName = param.get(0);
        String name = param.get(1);
        String[] parts = name.split(" ");
        String firstName = parts[0];
        String lastName = parts[1];

        System.out.println(courseName);
        System.out.println(firstName);
        System.out.println(lastName);

        EntityManagerFactory emfactory = Persistence.createEntityManagerFactory("StudentPU");
        entitymanager = emfactory.createEntityManager();

        Query query = entitymanager.createQuery("select tsc.mark "
        + "from TblStudentcourse tsc, TblStudents ts, TblCourses tc "
        + "where ts.id=tsc.tblStudentcoursePK.studentid and "
        + "tc.id=tsc.tblStudentcoursePK.courseid and "
        + "ts.firstname = '" + firstName + "' and "
        + "ts.lastname = '" + lastName + "' and "
        + "tc.coursename = '" + courseName + "'");

        Integer studentMark = (Integer)query.getSingleResult();
        System.out.println(studentMark);

        Query query2 = entitymanager.createQuery("select tsc.mark from TblStudentcourse tsc");
        List<Integer> list = query2.getResultList();

        entitymanager.close();

        Collections.sort(list);

        double median = median(list);
        System.out.println(median);

        int result = 0;
        if(studentMark > median){
            result = (int)Math.round((studentMark - median)/median * 100);
            System.out.println(result + "%");
        }
        else if(studentMark == median){
            System.out.println(0);
        }
        else{
            result = (int)Math.round((median - studentMark)/median * 100);
            System.out.println("-" + result + "%");
        }
    }

    static List<String> readFile(String filePath)
    {
        List<String> param = new ArrayList<>();
        try (BufferedReader bufferReader = new BufferedReader(new FileReader(filePath))) {
          for(String line; (line = bufferReader.readLine()) != null;)
          {
              param.add(line.trim());
              if(param.size() >= 2)
                  break;
          }
        } catch (FileNotFoundException e) {
          e.printStackTrace();
        } catch (IOException e) {
          e.printStackTrace();
        }
        return param;
    }

    static double median (List<Integer> a){
        int sum = 0;
        double mean = 0;
        int middle = a.size()/2;

        if (a.size() > 0) {
            for (Integer i : a) {
                sum += i;
            }
            mean = sum / (a.size() * 1.0);

            if (a.size() % 2 == 1)
                return a.get(middle);
            else
                return (a.get(middle-1) + a.get(middle)) / 2.0;
        }
        return 0;
    }
}