#include <bits/stdc++.h>

using namespace std;

const int NMAX = 1e6;
const int VMAX = 2 * NMAX;

pair <int, int> edges[VMAX + 1];

long long cod[NMAX + 1];
int len[NMAX + 1];
int v[NMAX + 1];

void dfs( int node ) {
    if ( edges[node] == make_pair(0, 0) ) return;
    int l = edges[node].first, r = edges[node].second;
    len[l] = len[r] = len[node] + 1;
    cod[l] = cod[node] * 2;
    cod[r] = cod[node] * 2 + 1;

    dfs( l );
    dfs( r );
}


queue <pair<long long, int>> pq1;
queue <pair<long long, int>> pq2;

pair <long long, int> getMin() {
    if ( !pq2.empty() && ( pq1.empty() || pq2.front() < pq1.front() ) ) {
        auto p = pq2.front();
        pq2.pop();
        return p;
    }
    auto p = pq1.front();
    pq1.pop();
    return p;
}
int main() {
    ifstream fin( "huffman.in" );
    ofstream fout( "huffman.out" );
    int n;
    fin >> n;


    for ( int i = 1; i <= n; i ++ ) {
        fin >> v[i];
        pq1.push( {v[i], i} );
    }
    int m = n;
    while ( pq1.size() + pq2.size() > 1 ) {
        auto p1 = getMin(), p2 = getMin();

        edges[++m] = {p1.second, p2.second};

        pq2.push( {p1.first + p2.first, m} );
        if ( pq1.empty() ) {
            swap( pq1, pq2 );
        }
    }
    dfs( m );
    long long totalLen = 0;
    for ( int i = 1; i <= n; i ++ ) {
        totalLen += (long long)v[i] * len[i];
    }
    fout << totalLen << '\n';
    for ( int i = 1; i <= n; i ++ ) {
        fout << len[i] << ' ' << cod[i] << '\n';
    }
    return 0;
}