hello penzionerski world

import java.io.*;

public class Main {

    public static void main(String[] args) {
        String source = "D:\\Projects\\Java projects\\OS-lab01-04\\resources\\rezultati.csv";
        String destination = "D:\\Projects\\Java projects\\OS-lab01-04\\resources\\rezultati.tsv";

        BufferedReader br = null;
        BufferedWriter bw = null;

        try {
            br = new BufferedReader(new FileReader(source));
            String s = br.readLine();
            String[] brojKoloni = s.split(",");
            int brojOcenkiPoPredmet = brojKoloni.length - 1;
            int[] zbirOcenkiPoPredmet = new int[s.length()];
            int vkupnoStudenti = 0;

            bw = new BufferedWriter(new FileWriter(destination));
            bw.write(s.replace(",", "\t")+"\n");

            while ((s = br.readLine()) != null) {
                String[] oceniUcenik = s.split(",");
                int zbir = 0;
                vkupnoStudenti++;

                for (int i = 1; i < oceniUcenik.length; i++) {
                    zbir += Integer.parseInt(oceniUcenik[i]);
                    zbirOcenkiPoPredmet[i] += Integer.parseInt(oceniUcenik[i]);
                }

                System.out.println("Prosekot na studentot " + oceniUcenik[0] + " e: " + (int) zbir / brojOcenkiPoPredmet);

                bw.write(s.replace(",", "\t")+"\n");

            }

            for(int i=1; i<brojKoloni.length; i++){
                System.out.println("Predmetot " + brojKoloni[i] + " ima prosek: " + (int)(zbirOcenkiPoPredmet[i]/vkupnoStudenti));
            }
            br.close();
            bw.flush();
            bw.close();
        }
        catch (IOException e){}

    }
}