Problem:
Score : 400 points

Problem Statement

There are N empty boxes arranged in a row from left to right.
The integer i is written on the i-th box from the left (1 \leq i \leq N).

For each of these boxes, Snuke can choose either to put a ball in it or to put nothing in it.

We say a set of choices to put a ball or not in the boxes is good when the following condition is satisfied:

For every integer i between 1 and N (inclusive), the total number of balls contained in the boxes with multiples of i written on them is congruent to a_i modulo 2.

Does there exist a good set of choices? If the answer is yes, find one good set of choices.

Constraints

All values in input are integers.

1 \leq N \leq 2 \times 10^5

a_i is 0 or 1.

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

If a good set of choices does not exist, print -1.

If a good set of choices exists, print one such set of choices in the following format:

M
b_1 b_2 ... b_M

where M denotes the number of boxes that will contain a ball, and b_1,\ b_2,\ ...,\ b_M are the integers written on these boxes, in any order.

Sample Input 1

3
1 0 0

Sample Output 1

1
1

Consider putting a ball only in the box with 1 written on it.

There are three boxes with multiples of 1 written on them: the boxes with 1, 2, and 3. The total number of balls contained in these boxes is 1.

There is only one box with a multiple of 2 written on it: the box with 2. The total number of balls contained in these boxes is 0.

There is only one box with a multiple of 3 written on it: the box with 3. The total number of balls contained in these boxes is 0.

Thus, the condition is satisfied, so this set of choices is good.

Sample Input 2

5
0 0 0 0 0

Sample Output 2

0

Putting nothing in the boxes can be a good set of choices.

Solution in Python (3.4.3) (judge verdict: Runtime Error)

#AGC018-A
if False:
    import fractions

    N,K=map(int,input().split())
    A=[int(i) for i in input().split()]
    MAX=max(A)
    GCD=A[0]
    for a in A:
        GCD=fractions.gcd(a,GCD)
    if K%GCD==0 and K<=MAX:
        print('POSSIBLE')
    else:
        print('IMPOSSIBLE')

#ABC134-D
if True:
    M=int(input())
    B=[int(i) for i in input().split()]
    fact=[[1] for i in range(M)]
    for i in range(2,M+1):
        k=2
        while k*i<=M:
            fact[k*i-1].append(i)
            k+=1
    # print(fact)
    ANS=[]
    PAL=[0 for i in range(M)]
    for i in reversed(range(M)):
        if 2*(i+1)>M:
            PAL[i]+=B[i]
            if B[i]==1:
                ANS.append(i+1)
        else:
            if PAL[i]!=B[i]:
                PAL[i]=(PAL[i]+1)%2
                ANS.append(i+1)
        for j in fact[i]:
                PAL[j]=(PAL[j]+PAL[i])%2
            
            
    print(len(ANS))
    print(' '.join(map(str,ANS)))