下面是我的程式:

def sieve_of_eratosthenes(limit):
    is_prime = [True] * (limit + 1)
    is_prime[0] = is_prime[1] = False

    p = 2
    while p * p <= limit:
        if is_prime[p]:
            for multiple in range(p * p, limit + 1, p):
                is_prime[multiple] = False
        p += 1

    primes = [p for p, prime in enumerate(is_prime) if prime]
    return primes

limit = 1000000
primes = sieve_of_eratosthenes(limit)
while True:
    a = int(input())
    if a!=0:
        if a in primes:
            print('0')
        else:
            print('1')
    else:
        break
   救我!大神!

1.

    primes = [p for p, prime in enumerate(is_prime) if prime]
    return primes

...

        if a in primes:

2.

while True:
    a = int(input())

1. primes是list，a in primes比較慢，可以改用set

2.  可以改成

for i in sys.stdin:
    a = int(i)