import subprocess
import multiprocessing as mp

def run(cmd):
    with open(cmd[-1], 'w') as f:
        return subprocess.run(cmd[:-1], stdout=f)

numbers = []
i = 100000000
for _ in range(10):
    numbers.append(i)
    i //= 2

commands = [['./a.out', str(x), str(x) + '.txt'] for x in numbers]
nproc = 2
pool = mp.Pool(nproc)
pool.map(run, commands)