1.12.3.java

gistfile1.txt

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

class ParallelPrimeFinder {
    @SuppressWarnings("unchecked")
    public static List<Long> execute(int t, long l, long r) throws InterruptedException {
        long rangeLength = r - l;
        ExecutorService executor = Executors.newFixedThreadPool(t);
        List<Future<List<Long>>> futures = new ArrayList<Future<List<Long>>>();

        long chunkSize = rangeLength / t;
        long currentNumber = l;
        for (int i = 0; i < t; i++) {
            long start = currentNumber;

            long end = currentNumber + chunkSize;
            currentNumber = end + 1;
            if (i == t - 1) {
                end = r;
            }
            long finalStart = start;
            long finalEnd = end;
            futures.add(executor.submit(() -> checkIfSimpleNumberAndAddToList(finalStart, finalEnd)));
        }
        executor.shutdown();

        // Собираем результаты
        List<Long> result = new ArrayList<Long>(List.of());
        try {
            for (Future<List<Long>> future : futures) {
                result.addAll(future.get());
            }
        } catch (ExecutionException e) {
            e.printStackTrace(); // Обработка ошибок выполнения
        } finally {
            executor.shutdown(); // Завершаем работу пула потоков
        }
        result.sort(null);
        return result;

    }

    private static List<Long> checkIfSimpleNumberAndAddToList(long start, long end) {
        List<Long> outList = new ArrayList<Long>(List.of());
        for (long j = start; j <= end; j++) {
            if (isPrime(j)) {
                outList.add(j);
            }

        }
        return outList;
    }

    private static boolean isPrime(long number) {
        if (number == 1) {
            return false;
        }
        boolean isPrime = true;
        for (int i = 2; i < number; i++) {
            if (number % i == 0) {
                isPrime = false;
                break;
            }
        }
        return isPrime;
    }
}