#include <bits/stdc++.h>

using namespace std;

using int64 = long long;

int N, M, X[5];
unordered_map< int, int64 > dp;
const int64 mod = 100000000000000007;

int main() {
  cin >> N >> M;
  for(int i = 0; i < M; i++) cin >> X[i];

  dp[0] = 1;
  for(int k = 0; k < N; k++) {
    if(dp.count(k)) {
      for(int i = 0; i < M; i++) {
        if(k + X[i] < N) {
          dp[k + X[i]] += dp[k];
          if(dp[k + X[i]] >= mod) dp[k + X[i]] -= mod;
        }
      }

      if(k == N - 1) {
        cout << dp[N - 1] << endl;
        return 0;
      }
      dp.erase(k);
    }

    if(k == N - 1) {
      cout << dp[N - 1] << endl;
      return 0;
    }
  }
}