# Multiprocessing:  Sharing data between processes (a Value or Array memory share must be created as processes do not share data by default)
from multiprocessing import Process, Value, Array, Lock
import os
import time

def add_100(numbers, lock):
    for _ in range(100):
        time.sleep(0.01)
        for i in range(len(numbers)):
            with lock:
                numbers[i] += 1
    print(f'Process {os.getpid()} has finished execution.')

if __name__ == "__main__":
    lock = Lock()
    shared_array = Array('d', [0.0, 100.0, 200.0, 300.0, 400.0])

    print('Array at the beginning is: ', list(shared_array))
    p1 = Process(target=add_100, args=(shared_array, lock))
    p2 = Process(target=add_100, args=(shared_array, lock))
    p1.start()
    p2.start()
    p1.join()
    p2.join()
    print('Array at the end is: ', list(shared_array))