#include <fstream>

using namespace std;

ifstream cin("huffman.in");
ofstream cout("huffman.out");

const int LIM=2000005;
int n, id=1, p, u, lvl=-1, val;
long long tot;
struct nod
{
    int val, st, dr;
} arb[LIM];
struct cell
{
    int lvl, val;
} ans[LIM/2];
void preord(int nod)
{
    lvl++;
    if(nod<=n)
    {
        ans[nod].lvl=lvl;
        ans[nod].val=val;
        tot+=(long long)ans[nod].lvl*arb[nod].val;
        lvl--;
        return;
    }
    val<<=1;
    preord(arb[nod].st);
    val++;
    preord(arb[nod].dr);
    val>>=1;
    lvl--;
}
int main()
{
    cin>>n;
    for(int i=1; i<=n; ++i)
        cin>>arb[i].val;
    p=n+1, u=n;
    for(int i=1; i<n; ++i)
    {
        int fius, fiud;
        if(p>u or (id<=n and arb[id].val<arb[p].val))
            fius=id, id++;
        else
            fius=p, p++;
        if(p>u or (id<=n and arb[id].val<arb[p].val))
            fiud=id, id++;
        else
            fiud=p, p++;
        u++;
        arb[u].val=arb[fius].val+arb[fiud].val;
        arb[u].st=fius;
        arb[u].dr=fiud;
    }
    preord(2*n-1);
    cout<<tot<<'\n';
    for(int i=1; i<=n; ++i)
        cout<<ans[i].lvl<<' '<<ans[i].val<<'\n';
    return 0;
}