#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;
#define PB push_back
const int N=1e5+10;
int main(){
    vector<int> v,t;
    int minus=0,n,a[N];
    scanf("%d",&n);
    for(int i=1;i<=n;i++)scanf("%d",&a[i]);
    for(int i=1;i<=n;i++)if(a[i]==-1){
        minus=i;
        break;
    }
    for(int i=1;i<=n;i++)if(a[i]==2)v.PB(i);
    else if(a[i]==-2)t.PB(i);
    if(t.size()&1){
        if(minus>0){
            v.PB(minus);
            for(int i:t)v.PB(i);
        }
        else{
            for(int i:t)v.PB(i);
            v.pop_back();
        }
    }
    else for(int i:t)v.PB(i);
    sort(v.begin(),v.end());
    printf("%ld\n",v.size());
    for(int i:v)printf("%d\n",i);
}

### Prompt

In Cpp, your task is to solve the following problem:

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

### Response

```cpp
#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;
#define PB push_back
const int N=1e5+10;
int main(){
    vector<int> v,t;
    int minus=0,n,a[N];
    scanf("%d",&n);
    for(int i=1;i<=n;i++)scanf("%d",&a[i]);
    for(int i=1;i<=n;i++)if(a[i]==-1){
        minus=i;
        break;
    }
    for(int i=1;i<=n;i++)if(a[i]==2)v.PB(i);
    else if(a[i]==-2)t.PB(i);
    if(t.size()&1){
        if(minus>0){
            v.PB(minus);
            for(int i:t)v.PB(i);
        }
        else{
            for(int i:t)v.PB(i);
            v.pop_back();
        }
    }
    else for(int i:t)v.PB(i);
    sort(v.begin(),v.end());
    printf("%ld\n",v.size());
    for(int i:v)printf("%d\n",i);
}

```