#include "bits/stdc++.h"

//speed coding

#define mp make_pair
#define cve(a) for (auto i : a) {cout << i << " ";  } cout << "\n";
#define f first
#define s second
#define loop(i, x, n) for (int i = x; i < n; i++)
#define joop(x, n) for (ll j = x; j < n; j++)
#define err cout << "ERROR" << endl;
#define all(x) x.begin(), x.end()
#define pb push_back
#define sz(x) x.size()

// types
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
typedef long long ll;

// types of data
#define inf 1000000000
#define infll 1000000000000000000
#define mod 998244343

//#define DEBUG 1
using namespace std;

char dp[111][111][10011] = {0};
ll a[110];
void solve() {
    int  n;
    cin >> n;
    int  m = 0;
    loop(i, 0, n) {
        cin >> a[i];
        m += a[i];
    }
    if (m % 2 != 0 || n % 2 != 0) {
        cout << -1;
        return;
    }
    loop(i, 0, n + 1) {
        dp[i][0][0] = 1;
    }
    loop(pref, 1, n + 1) {
        loop(cnt, 1, pref + 1) {
            loop(sum, 1, m + 1) {
                dp[pref][cnt][sum] = dp[pref - 1][cnt][sum] || dp[pref-1][cnt-1][sum - a[pref - 1]];
            }
        }
    }
    int sum = m / 2;
    int cnt = n / 2;
    int pref = n;
    if (dp[pref][cnt][sum] == 0) {
        cout << -1;
        return;
    }
    set<int> st; // max 100
    while (sum != 0) {
        if (dp[pref - 1][cnt - 1][sum - a[pref - 1]] && sum-a[pref - 1] >= 0) {
            st.insert(pref);
            cout << pref << " ";
            sum -= a[pref - 1];
            cnt--;
        }
        pref--;
    }
    cout << endl;

    loop(i, 1, n + 1) {
        if (st.count(i) == 0) {
            cout << i << " ";
        }
    }
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
#ifdef DEBUG
    freopen("text.txt", "r", stdin);
#else
#endif
    solve();
    return 0;
}