# multiprocessing.py

# multiprocessing.py

import time
import multiprocessing

def calculate_sum_of_squares(n):
    return sum(3 for i in range(1, n+1))

def calculate_sum_of_squares_parallel(n, num_processes):
    # num_processes = multiprocessing.cpu_count()
    chunk_size = n // num_processes
    print(chunk_size)

    processes = []
    results = multiprocessing.Array('i', num_processes)

    for i in range(num_processes):
        chunk = chunk_size
        if not i:
            chunk = chunk_size + (n - chunk_size * num_processes)
        p = multiprocessing.Process(target=worker, args=(chunk, i, results))
        processes.append(p)
        p.start()

    for p in processes:
        p.join()

    return sum(results)

def worker(chunk_size, index, results):
    result = calculate_sum_of_squares(chunk_size)
    results[index] = result

def main():
    print(f"Number of processors: {multiprocessing.cpu_count()}\n")
    for n in (1000000, 50000000):
        start_time = time.time()
        result_serial = calculate_sum_of_squares(n)
        serial_time = time.time() - start_time

        result_parallel = {}
        parallel_time = {}
        for i in range(2,9,2):
            start_time = time.time()
            result_parallel[i] = calculate_sum_of_squares_parallel(n, i)
            parallel_time[i] = time.time() - start_time

        print(f"\nSerial result:   {result_serial}    Time: {serial_time} seconds\n\tWorkers: None\n")
        for i in range(2,9,2):
            print(f"Parallel result: {result_parallel[i]}    Time: {parallel_time[i]} seconds\n\tWorkers:{i}\n")

if __name__ == '__main__':
    main()