#include <cstdio>
#include <queue>

using namespace std;

const int N=1000001;

struct nod{
	int poz;
	int  val;
	nod *left,*right;
}*R;

int n,textsize,initial[N];
long long code[N],rez;
short int length[N];
queue<nod *>Q1,Q2;

inline nod* extractmin(){
	nod* minim;
	if(Q2.empty()){
		minim=Q1.front();
		Q1.pop();
		return minim;
	}
	if(Q1.empty()){
		minim=Q2.front();
		Q2.pop();
		return minim;
	}
	if(Q2.front()->val<Q1.front()->val){
		minim=Q2.front();
		Q2.pop();
		return minim;
	}
	minim=Q1.front();
	Q1.pop();
	return minim;
}


void Buildtree(){
	int inputvalue;
	int i;
	freopen("huffman.in","r",stdin);
	scanf("%d",&n);
	for(i=1;i<=n;++i){
		scanf("%d",&inputvalue);
		initial[i]=inputvalue;
		nod *aux;
		aux=new nod;
		aux->poz=i;
		aux->val=inputvalue;
		aux->left=NULL;
		aux->right=NULL;
		Q1.push(aux);
	}

	nod *a,*b,*aux;
	for(i=1;i<n;++i){
		a=extractmin();
		b=extractmin();
		aux=new nod;
		aux->val=a->val+b->val;
		aux->poz=0;
		aux->left=a;
		aux->right=b;
		Q2.push(aux);
	}
	R=extractmin();
}

inline void Huffman(nod *a,long long cod,int codesize){
	if(a->poz!=0){
		code[a->poz]=cod;
		length[a->poz]=codesize;
		rez+=(initial[a->poz]*codesize);
		return;
	}
	Huffman(a->left,cod*2,codesize+1);
	Huffman(a->right,cod*2+1,codesize+1);
}

void Result(){
	int i;
	freopen("huffman.out","w",stdout);
	printf("%lld\n",rez);
	for(i=1;i<=n;++i){
		printf("%d %lld\n",length[i],code[i]);
	}
}

int main(){
	Buildtree();
	Huffman(R,0,0);
	Result();
	return 0;
}