// Huffman cu doua cozi, O(n)

#include <stdio.h>

using namespace std;

#define maxn 1000100
#define inf 1LL * 1000000000 * 1000000000

struct NOD {
    long long v;
    long f[2];
} nod[2 * maxn];

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

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

void solve() {
    l[0] = l[1] = 1;
    r[0] = n;
    // while (l[0] + l[1] <= r[0] + r[1]) {
    for (k = n + 1; k <= 2 * n - 1; k++) {
        for (j = 0; j < 2; j++) {
            p = 0;
            m = inf;
            for (i = 0; i < 2; i++) {
                if (nod[q[i][l[i]]].v < m && l[i] <= r[i]) {
                    p = i;
                    m = nod[q[i][l[i]]].v;
                }
            }
            nod[k].f[j] = q[p][l[p]];
            nod[k].v += nod[q[p][l[p]]].v;
            l[p]++;
        }
        sol += nod[k].v;    
        q[1][++r[1]] = k;
    }
    df(k, 0, 0);
}

int main() {
    freopen("huffman.in", "r", stdin);
    freopen("huffman.out", "w", stdout);
    scanf("%d", &n);
    for (i = 1; i <= n; i++) {
        scanf("%d", &nod[i].v);
        q[0][i] = i;
    }
    solve();
    printf("%lld\n", sol);
    for (i = 1; i <= n; i++) {
        printf("%d %lld\n", lg[i], b[i]);
    }
    return 0;
}