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

std::vector< std::pair<int, int> > edges;
int free_pos = 1;
void v_to_tree(int v, std::vector<int> & degrees) {
    while(degrees[v]) {
        degrees[v]--;
        degrees[free_pos]--;
        edges.push_back(std::make_pair(v, free_pos));
        v_to_tree(free_pos++, degrees);
    }
}

int main() {
    std::ios_base::sync_with_stdio(false);
    int best_change = 2, n;
    std::cin >> n;
    std::vector<int> best{1, 1}, A(n + 1), pref_A(n + 1, 0);
    for(int i = 0; i < n; i++) std::cin >> A[i + 1];
    std::sort(A.begin() + 1, A.end());
    for(int i = 1; i < n + 1; i++)
        pref_A[i] = A[i] + pref_A[i - 1];
    for(int v_count = 2; v_count <= n; v_count++) {
        if(v_count > 2) break;
        int needed_degree = 2 * v_count - 2;
        int a = 1, b = n + 1 - v_count, c;
        while(a < b) {
            c = (a + b) / 2;
            if(pref_A[c + v_count - 1] - pref_A[c - 1] < needed_degree)
                a = c + 1;
            else
                b = c;
        }
        /*
        std::cout << a << " here \n";
        for(int k = 0; k < 10; k++)
            std::cout << pref_A[k] << " ";
        std::cout << "\n";
        */
        int diff = pref_A[a + v_count - 1] - pref_A[a - 1];
        if(diff == needed_degree) {
            best_change = 0;
            best = std::vector<int>(A.begin() + a, A.begin() + a + v_count);
        } else if(diff > needed_degree) {
            if(best_change == 2 && A[a + v_count - 1] > (diff - needed_degree)) {
                best_change = 1;
                best = std::vector<int>(A.begin() + a, A.begin() + a + v_count);
                best[best.size() - 1] -= (diff - needed_degree);
            }
        } else {
            if(best_change == 2) {
                best_change = 1;
                best = std::vector<int>(A.begin() + a, A.begin() + a + v_count);
                best[0] -= (diff - needed_degree);
            }
        }

        if(a > 1) {
            diff = pref_A[a + v_count - 2] - pref_A[a - 2];
            if(best_change == 2) {
                best_change = 1;
                best = std::vector<int>(A.begin() + a - 1, A.begin() + a + v_count - 1);
                best[0] -= (diff - needed_degree);
            }
        }
    }

    std::sort(best.begin(), best.end());
    std::reverse(best.begin(), best.end());
    /*
    std::cout << best_change << "\n";
    std::cout << best.size() << "\n";
    for(int i = 0; i < best.size(); i++)
        std::cout << best[i] << " ";
    std::cout << std::endl;
    */
    v_to_tree(0, best);

    std::cout << best_change << "\n";
    std::cout << best.size() << "\n";
    for(int i = 0; i < edges.size(); i++)
        std::cout << edges[i].first + 1 << " " << edges[i].second + 1 << "\n";

    return 0;
}