#include <cstdio>
#define maxn 1000100
#define inf 1LL*1000000000*1000000000
using namespace std;
struct nod{
    long long v;
    long f[2];
} nod[2*maxn];

long n,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()
{
    long k=n;
    l[0]=l[1]=1;
    r[0]=n;
    while(l[0]+l[1]<=r[0]+r[1])
    {
        ++k;
        for(long j=0;j<2;j++)
        {
            p=0;
            m=inf;
            for(long 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(long i=1;i<=n;i++)
    {
        scanf("%d", &nod[i].v);
        q[0][i]=i;
    }
    solve();
    printf("%lld\n", sol);
    for(long i=1;i<=n;i++)
        printf("%d %lld\n", lg[i], b[i]);
    return 0;
}