#include <bits/stdc++.h>
using namespace std;
// define
#define int long long
#define UNIQUE(v) v.erase(unique(all(v)), v.end());
#define ZIP(v) sort(all(v)),UNIQUE(v)
#define ADD(a, b) a = (a + b) % mod
#define SUB(a, b) a = (a+mod-b)%mod
#define MUL(a, b) a = (((a)%mod) * ((b)%mod)) % mod
#define rollcall cout << "I'm Sucu." << endl;
#define repi(i,m,n) for(int i = m;i < n;i++)
#define drep(i,n,m) for(int i = n;i >= m;i--)
#define rep(i,n) repi(i,0,n)
#define rrep(i,n) repi(i,1,n+1)
#define chmin(x,y) x = min(x,y)
#define chmax(x,y) x = max(x,y)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(), v.rend()
#define dmp(x,y) make_pair(x,y)
#define pb(x) push_back(x)
#define pf(x) push_front(x)
#define fi first
#define se second
// debug
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p){
  os << "(" << p.first << "," << p.second << ")";return os;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v){
  for (auto it = v.begin();it != v.end();++it){
    if(it != v.begin())os << " ";os << *it;
      }return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const map<T, U> &mp){
  for(auto x: mp)os << "(" << x.first << "," << x.second << ")" << endl;
  return os;
}
template<typename T, int SIZE>
int array_length(const T (&)[SIZE]){return SIZE;}
template<typename T, int N>
void PRINTF(const T (&a)[N], int s = N, int t = -1, bool f = true){
	if(t == -1){rep(i,s){if(i)cout << " ";cout << a[i];}}
	else repi(i,s,t){if(i!=s)cout << " ";cout << a[i];}
	if(f)cout << "\n";
}
template<typename T, int N1, int N2>
void PRINTF(const T (&a)[N1][N2], int h = N1, int w = N2){
	rep(i,h){rep(j,w){cout << a[i][j] << " \n"[j==w-1];}}
}
string substr(const string &str, int S1, int S2 = -1){
  if(S2 == -1)return str.substr(S1);
  return str.substr(S1, S2-S1);
}
// typedef
typedef complex<double> Point;
typedef pair<int, int> P;
typedef pair<int, P> PP;
typedef pair<P, int> Pi;
typedef vector<int> vi;
typedef deque<int> dq;
const int inf = 1e9+7;
const int INF = 1e18+7;


int a[200000];
string dp[200000];
int mp[] = {0, 2, 5, 5, 4, 5, 6, 3, 7, 6};
string calc(string str, char s){
  if(str == "0"){string st;st.pb(s);return st;}
  str = "9" + str;
  // cout << str << endl;
  // cout << str.substr(1, 1) + "7" << str.substr(0, 1) << endl;
  int l = 0, r = str.size()-1;
  while(l+1 < r){
    int mid = (l+r)/2;
    // printf("%lld %lld %lld", num, fac[mid+1]);
    // printf("%lld %lld\n", l, r);
    if(s < str[mid])l = mid;
    else r = mid;
  }
  // printf("%lld\n", l);
  string res = str.substr(1, l) + s + str.substr(l+1, str.size()-1-l);
  return res;
}

bool ok(string str1, string str2){
  if(str1.size() < str2.size())return true;
  else if(str1.size() > str2.size())return false;
  return str1 < str2;
}

signed main(){
  int n, m;
  // cout << calc("3", '7') << endl;
  scanf("%lld%lld", &n, &m);
  rep(i,m)scanf("%lld", &a[i]);
  rrep(i,n)dp[i] = "-";dp[0] = "0";
  sort(a, a+m);
  
  rrep(i,n){
    int idx = 0;
    rep(j,m){
      int s = a[j];
      if(i < mp[s] or dp[i-mp[s]] == "-")continue;
      string res = calc(dp[i-mp[s]], s+'0');
      if(ok(dp[i], res))dp[i] = res;
    }
  }
  // rrep(i,n)cout << dp[i] << " ";cout << endl;
  cout << dp[n] << endl;
  return 0;
}








Measured memory_bytes: 34432