#include <iostream>

#include <bits/stdc++.h>

#include <vector>

using namespace std;

map<int, string> ans;

class Node{

public:

int freq;

Node* left = NULL;

Node* right = NULL;

};

Node* create_node(int freq, Node* left, Node* right);

vector<Node*> huffman(vector<Node*> val);

bool sortbyfreq(Node* a, Node* b){return (a->freq <= b->freq);}

void encode(Node* tree, string str);

int main(){

int N;

cin >> N;

int freq[N];

for (int i = 0; i < N; i ++){

cin >> freq[i];

}

vector<Node*> vec(N);

for (int i = 0; i < N; i ++){

vec[i] = new Node();

vec[i]->freq = freq[i];

}

while (vec.size() > 1){

vec = huffman(vec);

}

encode(vec[0], "");

cout << N << endl;

for (int i = 0; i < N; i ++){

cout << ans[freq[i]] << " ";

}

}

Node* create_node(int freq, Node* left, Node* right){

Node* root = new Node();

root->freq = freq;

root->left = left;

root->right = right;

return root;

}

vector<Node*> huffman(vector<Node*> val){

sort(val.begin(), val.end(), sortbyfreq);

vector<Node*>::iterator it = val.begin();

Node* mergenode = create_node(val[0]->freq + val[1]->freq, val[0], val[1]);

val.erase(it);

val.erase(it);

val.push_back(mergenode);

return val;

}

void encode(Node* tree, string str){

if (tree->left == NULL && tree->right == NULL) ans.insert(pair<int, string>(tree->freq, str));

if (tree->left) encode(tree->left, str + "0");

if (tree->right) encode(tree->right, str + "1");

}