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#include <bits/stdc++.h>

using namespace std;

int main() {
    int n;
    scanf("%d", &n);
    int cnt = 0;
    for (int i = 0; i < n; i++) {
        int x;
        scanf("%d", &x);
        if (x == 1) cnt++;
    }
    printf("%d\n", 2 - min(2, cnt));
    printf("2\n1 2\n");
    return 0;
}