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#include <algorithm>
#include <iostream>
#include <random>
#include <vector>

int main(int argc, char** argv) {
    uint32_t n = 0;
    std::cin >> n;

    uint32_t num_of_ones = 0;
    uint32_t tmp = 0;
    for (uint32_t idx = 0; idx < n; idx++) {
        std::cin >> tmp;
        if (tmp == 1) num_of_ones += 1;
    }

    if (num_of_ones >= 2) std::cout << "0" << std::endl;
    else if (num_of_ones == 1) std::cout << "1" << std::endl;
    else std::cout << "2" << std::endl;

    std::cout << "2" << std::endl;
    std::cout << "1 2" << std::endl;
    
    return 0;
}