#include <bits/stdc++.h>
 
#define pb push_back
#define mp make_pair
#define mod 1000000007
#define PI 3.141592653589793;
 
using namespace std;

int a[400001];
map<int, int> b;
int n,x;

int main() {
    //freopen("data.in", "r", stdin);
    //freopen("data.out", "w", stdout);

    scanf("%d", &n);
    for(int i = 0; i<n; i++){
        scanf("%d", &a[i]);
        a[i]%=n;
        if(!a[i]) {
            printf("%d\n%d", 1, i+1);
            return 0;
        }
        b[a[i]] = i+1;
    }

    for(int i=0; i < n; i++){
        x = a[i];
        for(int j = i+1; j<n; j++){
            x+=a[j];
            x%=n;
            if(b[n-x]){
                printf("%d\n", j-i+2);
                for(int k =i; k<=j; k++){
                    printf("%d ", k+1);
                }
                printf("%d", b[n-x]);
                return 0;
            }
        }
    }
}