p01968 Hierarchical Calculator
B： 階層的計算機 (Hierarchical Calculator)

Problem

Ebi-chan has N formulae: y = a_i x for i =1, ..., N (inclusive). Now she considers a subsequence of indices with length k: s_1, s_2, ..., s_k. At first, let x_0 be 1 and evaluate s_1-th formulae with x = x_0. Next, let x_1 be the output of s_1 and evaluate s_2-th formulae with x = x_1, and so on.

She wants to maximize the final output of the procedure, x_{s_k}. If there are many candidates, she wants the """shortest one""". If there are still many candidates, she wants the """lexicographically smallest one""".

Sequence s is lexicographically smaller than sequence t, if and only if either of the following conditions hold:

* there exists m < |s| such that s_i = t_i for i in 1 to m (inclusive) and s_{m+1} < t_{m+1}, or
* s_i = t_i for i in 1 to |s| (inclusive) and |s| < |t|,



where |s| is the length of the s.

Input


N
a_1 a_2 $\cdots$ a_N


Constraints

* 1 \leq N \leq 60
* -2 \leq a_i \leq 2 for i=1, ...,N (inclusive)
* Every input is given as the integer.



Output

Output k+1 lines. First line, the length of the sequence, k. Following k lines, the index of the i-th element of the subsequence, s_i (one element per line).

Sample Input 1


4
2 0 -2 1


Sample Output for Input 1


1
1


She evaluates the first one and gets the maximum value 2.

Sample Input 2


3
2 -2 -2


Sample Output for Input 2


3
1
2
3


She evaluates all of them and gets the maximum value 8.

Sample Input 3


2
-1 0


Sample Output for Input 3


0

She evaluates none of them and gets the maximum value 0. Empty sequence is the shorter and lexicographically smaller than any other sequences.

Sample Input 4


5
-1 2 1 -2 -1


Sample Output for Input 4


3
1
2
4


She evaluates $\langle$ 1, 2, 4 $\rangle$ ones and gets the maximum value 4. Note that $\langle$ 2, 4, 5 $\rangle$ is not lexicographically smallest one.





Example

Input

4
2 0 -2 1


Output

1
1
```python
# -*- coding: utf-8 -*-
from collections import Counter
def inpl(): return tuple(map(int, input().split()))

N = int(input())
A = list(map(int, input().split()))

C = Counter(A)
if C[-2] % 2 == 0:
    ans = [i+1 for i, a in enumerate(A) if abs(a) == 2]
    print(len(ans))
    if len(ans):
        print(*ans, sep="\n")
elif C[-1] > 0:
    ans = [i+1 for i, a in enumerate(A) if abs(a) == 2] + [A.index(-1) + 1]
    print(len(ans))
    if len(ans):
        print(*sorted(ans), sep="\n")
else:
    d = N -A[::-1].index(-2)
    ans = [i+1 for i, a in enumerate(A) if abs(a) == 2]
    del ans[ans.index(d)]
    print(len(ans))
    if len(ans):
        print(*ans, sep="\n")

```