#include<bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define BIG 1000000010
#define repi(i,x,n) for(int i=x;i<n;i++)
#define rep(i,n) repi(i,0,n)
#define repn(i,n) for(int i=n;i>=0;i--)
typedef long long int ll;


int main(){
  int n,m;
  pair<int,int> a[60];
  vector<int> ans;
  cin>>n;
  rep(i,n){
    cin>>m;
    a[i]=make_pair(m,i+1);
  }
  sort(a,a+n);
  repn(i,n-1){
    if(a[i].first>1) ans.push_back(a[i].second);
    else break;
  }
  rep(i,n){
    if(a[i].first<0 && a[i].first!= -1){
      if(a[i+1].first<0){
	ans.push_back(a[i].second);
	ans.push_back(a[i+1].second);
	i++;
      }else break;
    }else break;
  }
  sort(ans.begin(),ans.end() );
  cout<<ans.size()<<endl;
  rep(i,ans.size() ){
    cout<<ans[i]<<endl;
  }
      
  

  return 0;
}


### Prompt

Generate a CPP solution to 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<bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define BIG 1000000010
#define repi(i,x,n) for(int i=x;i<n;i++)
#define rep(i,n) repi(i,0,n)
#define repn(i,n) for(int i=n;i>=0;i--)
typedef long long int ll;


int main(){
  int n,m;
  pair<int,int> a[60];
  vector<int> ans;
  cin>>n;
  rep(i,n){
    cin>>m;
    a[i]=make_pair(m,i+1);
  }
  sort(a,a+n);
  repn(i,n-1){
    if(a[i].first>1) ans.push_back(a[i].second);
    else break;
  }
  rep(i,n){
    if(a[i].first<0 && a[i].first!= -1){
      if(a[i+1].first<0){
	ans.push_back(a[i].second);
	ans.push_back(a[i+1].second);
	i++;
      }else break;
    }else break;
  }
  sort(ans.begin(),ans.end() );
  cout<<ans.size()<<endl;
  rep(i,ans.size() ){
    cout<<ans[i]<<endl;
  }
      
  

  return 0;
}


```