#include <cstdio>

using namespace std;

const int N = 1000100;
const long long inf = (1LL << 62);

struct nod {
    long long v;
    int f[2];
};

int n, i, j, k, p, l[2], r[2], q[2][N], lg[N];
long long b[N], m, sol;

nod v[2 * N];

void df(int poz, long long cod, int niv) {
    if (v[poz].f[0]) {
        df(v[poz].f[0], cod * 2, niv + 1);
        df(v[poz].f[1], cod * 2 + 1, niv + 1);
        return;
    }
    lg[poz] = niv;
    b[poz] = cod;
}

int main() {
    freopen("huffman.in", "r", stdin);
    freopen("huffman.out", "w", stdout);
    scanf("%d", &n);
    for (i = 1; i <= n; ++i) {
        scanf("%d", &v[i].v);
        q[0][i] = i;
    }
    k = n;
    l[0] = l[1] = 1;
    r[0] = n;
    while (l[0] + l[1] <= r[0] + r[1]) {
        k++;
        for (j = 0; j < 2; ++j) {
            p = 0;
            m = inf;
            for (i = 0; i < 2; ++i) {
                if (v[ q[i][ l[i] ] ].v < m && l[i] <= r[i]) {
                    p = i;
                    m = v[ q[i][ l[i] ] ].v;
                }
            }
            v[k].f[j] = q[p][ l[p] ];
            v[k].v += v[ q[p][ l[p] ] ].v;
            l[p]++;
        }
        sol += v[k].v;
        q[1][ ++r[1] ] = k;
    }
    df(k, 0, 0);
    printf("%lld\n", sol);
    for (i = 1; i <= n; ++i) {
        printf("%d %lld\n", lg[i], b[i]);
    }
    return 0;
}