Problem with task

package pl.codegym.task.task16.task1628; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List; import java.util.concurrent.atomic.AtomicInteger; public class Solution { public static volatile AtomicInteger readStringCount = new AtomicInteger(0); public static volatile BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); public static void main(String[] args) throws IOException { // Wczytuje liczbę ciągów int count = Integer.parseInt(reader.readLine()); // Inicjuje wątki ReaderThread consoleReader1 = new ReaderThread(); ReaderThread consoleReader2 = new ReaderThread(); ReaderThread consoleReader3 = new ReaderThread(); consoleReader1.start(); consoleReader2.start(); consoleReader3.start(); while (count > readStringCount.get()) { } consoleReader1.interrupt(); consoleReader2.interrupt(); consoleReader3.interrupt(); System.out.println("#1:" + consoleReader1); System.out.println("#2:" + consoleReader2); System.out.println("#3:" + consoleReader3); reader.close(); } public static class ReaderThread extends Thread { private List<String> result = new ArrayList<>(); public void run() { try { while (!isInterrupted()) { result.add(reader.readLine()); readStringCount.getAndIncrement(); if (isInterrupted()) return; } } catch (IOException e) { } } @Override public String toString() { return result.toString(); } } }