#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
using namespace std;
typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
const ll mod = 1000000007;
typedef double ld;
typedef complex<ld> Point;
const ll INF = mod * mod;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(iinclude<snt i=sta;i<=n;i++)
const ld eps = 1e-6;
const ld pi = acos(-1.0);
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;

int n;
void solve() {
	cin >> n;
	vector<int> a(n);
	rep(i, n)cin >> a[i];
	int chk = -1;
	rep(i, n) {
		if (a[i] == -1) {
			chk = i; break;
		}
	}
	if (chk >= 0) {

		vector<int> ans;
		vector<int> re;
		rep(i, n) {
			if (a[i] == 2) {
				ans.push_back(i);
			}
			if (a[i] == -2) {
				re.push_back(i);
			}
		}
		if (re.size() % 2)ans.push_back(chk);
		rep(i, re.size())ans.push_back(re[i]);
		sort(ans.begin(), ans.end());

		cout << ans.size() << endl;
		rep(i, ans.size()) {
			cout << ans[i]+1 << endl;
		}
	}
	else {
		vector<int> ans;
		vector<int> re;
		rep(i, n) {
			if (a[i] == 2) {
				ans.push_back(i);
			}
			if (a[i] == -2) {
				re.push_back(i);
			}
		}
		if (re.size() % 2)re.pop_back();
		rep(i, re.size())ans.push_back(re[i]);
		sort(ans.begin(), ans.end());
		cout << ans.size() << endl;
		rep(i, ans.size()) {
			cout << ans[i]+1 << endl;
		}
		
	}
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	solve();
	//stop
		return 0;
}
