#include<cstdio>
#define N 2000000
long long q[N];
int n,i,j,k,r[N],s[N],d[N],p[N];
int main()
{freopen("huffman.in","r",stdin);
freopen("huffman.out","w",stdout);
scanf("%d",&n);
for(i=1;i<=n;i++)
       scanf("%d",&r[i]),q[i]=N;
for(j=k=i=1;i<n;i++)
       {if(k<n&&r[k+1]<=q[j])
              q[i]=r[k]+r[k+1],s[i+n]=k,d[i+n]=k+1,k+=2;
       if(q[j+1]<=r[k]||k>n)
              q[i]=q[j]+q[j+1],s[i+n]=j+n,d[i+n]=j+n+1,j+=2;
       if(q[j]<=r[k]&&r[k]<=q[j+1])
              q[i]=r[k]+q[j],s[i+n]=k,d[i+n]=j+n,k++,j++;
       if(r[k]<=q[j]&&((k<n&&q[j]<=r[k+1])||n<=k))
              q[i]=r[k]+q[j],s[i+n]=j+n,d[i+n]=k,k++,j++;
       r[i+n]=q[i],q[0]+=q[i];}
printf("%lld\n",q[0]);
for(k=j=1,i=2*n-1;k<=j;i=r[k++])
        {p[s[i]]=p[d[i]]=p[i]+1,q[s[i]]=2*q[i],q[d[i]]=q[s[i]]+1;
        if(i>n)
                 r[j++]=s[i],r[j++]=d[i];}
for(i=1;i<=n;i++)
        printf("%d %lld\n",p[i],q[i]);
return 0;}