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#include <iostream>
#include <vector>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<int> degrees (n);
    for (int&d:degrees)cin>>d;
    vector<int>ones;
    vector<int>not_ones;
    for (int i=0;i<degrees.size();i++){
        if (degrees[i]==1)ones.push_back(i);
        else not_ones.push_back(i);
    }
    int k = 0;
    while (ones.size() < 2) {
        k++;
        ones.push_back(not_ones.back());
        not_ones.pop_back();
    }
    cout << k << endl;
    cout << 2 << endl;
    cout << 1 << " " << 2 << endl;
}