import numpy as np
from time import time
import multiprocessing


def task(matrix, start_j, stop_j, queue):
    size = len(matrix[0])
    if size == 2:  # Базовый случай: определитель 2x2
        det = matrix[0][0] * matrix[1][1] - matrix[1][0] * matrix[0][1]
        if queue is not None:
            queue.put(det)
        return det
    else:
        res = 0
        for j in range(start_j, stop_j):
            # Удаляем строку и столбец с помощью срезов (более эффективно)
            tmp = matrix[1:, :j]
            tmp = np.hstack((tmp, matrix[1:, j + 1:]))

            a = matrix[0][j]
            b = task(tmp, 0, len(tmp[0]), None)

            if j % 2 == 0:
                res += a * b
            else:
                res += a * b * (-1)

        if queue is not None:
            queue.put(res)
        return res


if __name__ == '__main__':
    sizes = [5, 6, 7, 8, 9, 10]
    threads_counts = [1, 4, 6, 8, 10]

    for threads in threads_counts:
        print(f'Количество потоков: {threads}')
        for size in sizes:
            matrix = np.random.randint(10, size=(size, size))

            offset = int(size / threads)
            offset_last = size % threads + offset

            processes = []
            queue = multiprocessing.Queue()
            start = time()
            for i in range(threads):
                start_ = i * offset
                stop_ = start_ + offset_last if i == threads - 1 else start_ + offset

                process = multiprocessing.Process(target=task, args=(matrix, start_, stop_, queue))
                processes.append(process)
                process.start()

            total_result = 0
            for p in processes:
                p.join()
                total_result += queue.get()

            stop = time()
            print(f'Размер: {size}x{size}, время выполнения: {stop - start} сек')

        print()