#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

constexpr int P = 1000000007;

int  x[100000];
int dp[100001];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int k;
    cin >> k;

    int n;
    cin >> n;

    for (int i = 0; i < n; i++) {
        cin >> x[i];
    }
    
    dp[0] = 1;
    for (int l = 1; l <= k; l++) {
        ll t = 0;
        for (int i = 0; i < n; i++) {
            if (x[i] > l) break;
            t += dp[l - x[i]];
        }
        dp[l] = t % P;
    }

    cout << dp[k] << endl;

    return 0;
}