#include<bits/stdc++.h>
using namespace std;

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

const int INF = 0x3f3f3f3f;
const int DIM = 1e6 + 5;
int arr[DIM * 2 + 5];

int N, pos, p, last;
long long sol;
pair<int,long long> ans[DIM * 2];
int st[2 * DIM], dr[2 * DIM];

void dfs( int nod, int lg ){

    ans[nod].first = lg;
    long long aux = ans[nod].second;

    if( nod > N )
        sol += arr[nod];

    if( st[nod] == 0 )
        return;

    ans[ st[nod] ].second = aux * 2;
    ans[ dr[nod] ].second = aux * 2 + 1;
    dfs( st[nod], lg + 1 );
    dfs( dr[nod], lg + 1 );
    return;
}

int main(){

    fin >> N;
    for( int i = 1; i <= N; i++ )
        fin >> arr[i];
    pos = N + 1;
    last = N;
    p = 1;

    for( int step = 1; step < N; step++ ){

        int s1 = INF, s2 = INF, s3 = INF;
        if( p + 1 <= N )
            s1 = arr[p] +  arr[p + 1];
        if( pos <= last && p <= N )
            s2 = arr[p] + arr[pos];
        if( pos + 1 <= last )
            s3 = arr[pos] + arr[pos + 1];

        if( s1 <= s2 && s1 <= s3 ){
            last++;
            st[last] = p;
            dr[last] = p + 1;
            arr[last] = s1;
            p += 2;
            continue;
        }

        if( s2 <= s3 && s2 <= s1 ){
            last++;
            st[last] = p;
            dr[last] = pos;
            arr[last] = s2;
            pos++;
            p++;
            continue;
        }

        if( s3 <= s1 && s3 <= s2 ){
            last++;
            st[last] = pos;
            dr[last] = pos + 1;
            arr[last] = s3;
            pos += 2;
            continue;
        }

    }

    dfs( last, 0 );
    /*
    for( int i = 1; i <= N; i++ )
        sol += 1LL * arr[i] * ans[i].first;
    */
    fout << sol << "\n";

    for( int i = 1; i <= N; i++ )
        fout << ans[i].first << " " << ans[i].second << "\n";
    return 0;
}