#include <iostream>
#include <cstdio>

#define NMAX 400005

using namespace std;

int s[NMAX] , c[NMAX];
int n , x;

void afis(int p1 , int p2) {
    cout << p2 - p1 + 1 << '\n';
    for(int i = p1 ; i <= p2 ; ++i) {
        cout << i << " ";
    }
}

int main() {
    #ifndef ONLINE_JUDGE
        freopen("input.txt" , "r" , stdin);
    #endif // ONLINE_JUDGE

    cin >> n;
    for(int i = 1 ; i <= n ; ++i) {
        cin >> x;
        s[i] = s[i - 1] + x;
        s[i] %= n;

        if(s[i] == 0) {
            afis(1 , i);
            return 0;
        }

        else {
            if(c[s[i]] == 0) {
                c[s[i]] = i;
            }

            else {
                afis(c[s[i]] + 1 , i);
                return 0;
            }
        }
    }
    return 0;
}