#include <fstream>
#include <queue>

using namespace std;
const int nmax = 1e6;

queue < pair < long long, int > > q1, q2;

struct node {
    int st, dr;
} a[2 * nmax];

long long code[2 * nmax];
int len[2 * nmax];
int f[nmax];


pair < long long, int > minim () {
    pair < long long, int > r;
    if ( q2.size () == 0 || ( q1.size() > 0 && q1.front() < q2.front() ) ) {
        r = q1.front ();
        q1.pop ();
    } else {
        r = q2.front ();
        q2.pop ();
    }
    return r;
}

void dfs ( int node, long long cod, int lun ) {
    if ( node == -1 )
        return;
    code[node] = cod;
    len[node] = lun;
    dfs ( a[node].st, cod * 2, lun + 1 );
    dfs ( a[node].dr, cod * 2 + 1, lun + 1 );
}

ifstream fin ( "huffman.in" );
ofstream fout ( "huffman.out" );

int main() {
    int n;
    fin >> n;

    for ( int i = 0; i < 2 * n; i++ )
        a[i].st = a[i].dr = -1;

    for ( int i = 0; i < n; i++ ) {
        fin >> f[i];
        q1.push ( { f[i], i } );
    }

    int ind = n;
    while ( q1.size() + q2.size() >= 2 ) {
        auto x = minim (), y = minim ();
        a[ind].st = x.second;
        a[ind].dr = y.second;
        q2.push ( { x.first + y.first, ind } );
        ind++;
    }

    dfs ( ind - 1, 0, 0 );

    long long s = 0;
    for ( int i = 0; i < n; i++ )
        s += ( long long ) f[i] * len[i];

    fout << s << '\n';
    for ( int i = 0; i < n; i++ )
        fout << len[i] << ' ' << code[i] << '\n';



    return 0;
}