#include <stdio.h>
#include <stdlib.h>
#define Inf 9000000000000000000LL

typedef struct Node {
    long long data;
    int ind;
    struct Node * left;
    struct Node * right;
} Node;

short p[1000010];
long long q[1000010];
long long lg=0;

void print (Node * k,int u,long long v)
{
    if (!k) return;
    if (!k->left&&!k->right) {
        p[k->ind]=u;
        q[k->ind]=v;
        lg+=u*k->data;
    }
    print (k->left,u+1,v<<1);
    print (k->right,u+1,(v<<1)+1);
}

int main () {
    FILE * in=fopen ("huffman.in","r");
    FILE * out=fopen ("huffman.out","w");
    short l=sizeof (Node);
    int i,n,c1=0,c2=0,d2=0;
    fscanf (in,"%d",&n);
    Node * t,*t1,*t2,*inf;
    Node ** k1=(Node**) malloc ((n+10)*4);
    Node ** k2=(Node**) malloc (((n<<1)+10)*4);
    for (i=0; i<n; i++) {
        t=(Node*) malloc (24);
        fscanf (in,"%lld",&t->data);
        t->ind=i;
        t->left=0;
        t->right=0;
        k1[i]=t;
    }
    k1[n]=malloc (24);
    k1[n]->data=Inf;
    inf=malloc (24);
    inf->data=Inf;
    k2[0]=inf;
    while (1) {
        t1=(k1[c1]->data<=k2[c2]->data ? k1[c1++] : k2[c2++]);
        t2=(k1[c1]->data<=k2[c2]->data ? k1[c1++] : k2[c2++]);
        if (t2->data==Inf) break;
        t=(Node*) malloc (24);
        t->data=t1->data+t2->data;
        t->left=t1;
        t->right=t2;
        k2[d2++]=t;
        k2[d2]=inf;
    }
    print (k2[c2-1],0,0);
    fprintf (out,"%lld\n",lg);
    for (i=0; i<n; i++) fprintf (out,"%d %lld\n",p[i],q[i]);
    fclose (in);
    fclose (out);
    return 0;
}