Buggy python submission (verdict: Time Limit Exceeded):
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    # box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in range(1,n+1)[::-1]:
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(i+1, end=" ")
        
if __name__ == "__main__":
    main()

Fixed submission:
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    # box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in range(1,n//2+1)[::-1]:
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(i+1, end=" ")
        
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in box[:n//2][::-1]:
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(box[i], end=" ")
        

if __name__ == "__main__":
    main()

Fixed submission:
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    # box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in range(1,n//2+1)[::-1]:
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(i+1, end=" ")
        
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in box[:n//2][::-1]:
        t = np.array(range(i, n+1, i))
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(box[i], end=" ")
        

if __name__ == "__main__":
    main()

Fixed submission:
import numpy as np

def main():
    n = int(input())
    a = np.zeros([n], dtype=int)
    # box = np.array(range(1,n+1))
    a = list(map(int, input().split(" ")))
    b = np.zeros_like(a)

    for i in range(n//2, n):
        if a[i] == 1:
            b[i] = 1

    for i in range(1,n//2+1)[::-1]:
        if np.sum(b[i-1::i])%2 != a[i-1]:
            b[i-1] = 1

    ball = np.where(b==1)[0]
    print(len(ball))
    for i in ball:
        print(i+1, end=" ")
        
if __name__ == "__main__":
    main()