#include <bits/stdc++.h>
using namespace std;

#define all(x) begin(x), end(x)
#ifdef CKISEKI
#define safe cerr << __PRETTY_FUNCTION__ << " line " << __LINE__ << "\n";
#define debug(a...) debug_(#a, a)
#define orange(a...) orange_(#a, a)
void debug_(auto s, auto ...a) {
  cerr << "\e[1;32m(" << s << ") = (";
  int f = 0;
  (..., (cerr << (f++ ? ", " : "") << a));
  cerr << ")\e[0m\n";
}
#include <experimental/iterator>
void orange_(auto s, auto L, auto R) {
  cerr << "\e[1;33m[ " << s << " ] = [ ";
  using namespace experimental;
  copy(L, R, make_ostream_joiner(cerr, ", "));
  cerr << " ]\e[0m\n";
}
#else
#define safe ((void)0)
#define debug(...) safe
#define orange(...) safe
#endif

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);


  int n, m;
  cin >> n >> m;
  vector<int> a(m);
  for (int i = 0; i < m; i++)
    cin >> a[i];


  using VI = vector<int>;
  set<VI> dp[11];

  {
    vector<int> s = {n};
    dp[0].insert(s);
  }

  for (int i = 0; i < m; i++) {
    for (auto v : dp[i]) {
      vector<set<VI>> cur(a[i] + 1);
      cur[0].insert(VI{});

      vector<size_t> sizes;
      for (size_t j = 0; j < v.size(); j++) {
        vector<set<VI>> nxt(a[i] + 1);
        for (int y = 0; y <= v[j]; y++) {
          for (int x = 0; x + y <= a[i]; x++) {
            for (auto u : cur[x]) {
              if (y)
                u.push_back(y);
              if (v[j] - y)
                u.push_back(v[j] - y);
              sort(all(u));
              nxt[x + y].insert(u);
            }
          }
        }
        cur = nxt;
        size_t s = 0;
        for (int x = 0; x <= a[i]; x++)
          s += cur[x].size();
        sizes.push_back(s);
      }

      for (auto u : cur[a[i]]) {
        dp[i + 1].insert(u);
      }
    }
    debug(dp[i].size());
  }

  debug(dp[m].size());

  int ans = 0;
  for (auto v : dp[m]) {
    int cnt = 0;
    for (int x : v)
      if (x == 1)
        ++cnt;
    ans = max(ans, cnt);
  }
  cout << ans << '\n';

  return 0;
}