#include<stdio.h>
#include<fstream>
using namespace std;
struct nod{
long long v;
int f[2];
}a[1000010];
long n,q[1000100][2],l[2],r[2];
long long sum[1000100],sol=0,lg[1000010];
void df(int x,int cod,int nivel){
if(a[x].f[0]){
    df(a[x].f[0],cod*2+1,nivel+1);
    df(a[x].f[1],cod*2,nivel+1);
    return;
}
sum[x]=cod;
lg[x]=nivel;
sol += nivel*a[x].v;
}
int main(){
freopen("huffman.in","r",stdin);
ofstream o("huffman.out");
scanf("%d",&n);
for(int i=1;i<=n;i++)scanf("%d",&a[i].v),q[i][0]=i;
int k=n;
l[0]=l[1]=1;
r[0]=n;
while(l[0]+l[1]<=r[1]+r[0]){
    k++;
    for(int i=0;i<2;i++){
        int p=0;
        long long m=1<<20;
        for(int j=0;j<2;j++){
            if(l[j]<=r[j]&&m>a[q[l[j]][j]].v){
                p=j;
                m=a[q[l[j]][j]].v;
            }
        }
        a[k].v+=m;
        a[k].f[i]=q[l[p]][p];
        l[p]++;
    }
    q[++r[1]][1]=k;
}
df(k,0,0);
o<<sol<<"\n";
for(int i=1;i<=n;i++)o<<lg[i]<<" "<<sum[i]<<"\n";
}