#include <bits/stdc++.h>
using namespace std;
const long long mod = 998244353, mod2 = 1e9 + 9, p1 = 5807, p2 = 8573;
const long long N = 2e4 + 5, M = 21;
const long double pi = acos(-1);
long long power(long long x, unsigned long long y, long long p) {
  long long res = 1;
  x = x % p;
  while (y > 0) {
    if (y & 1) res = (res * x) % p;
    y = y >> 1;
    x = (x * x) % p;
  }
  return res;
}
void MOD(long long *x) {
  if (*x >= mod) {
    *x -= (*x / mod) * mod;
  }
}
const int root = 15311432;
const int root_1 = 469870224;
const int root_pw = 1 << 23;
void fft(vector<int> &a, bool invert) {
  int n = a.size();
  for (int i = 1, j = 0; i < n; i++) {
    int bit = n >> 1;
    for (; j & bit; bit >>= 1) j ^= bit;
    j ^= bit;
    if (i < j) swap(a[i], a[j]);
  }
  for (int len = 2; len <= n; len <<= 1) {
    int wlen = invert ? root_1 : root;
    for (int i = len; i < root_pw; i <<= 1)
      wlen = (int)((1LL * wlen * wlen) % mod);
    for (int i = 0; i < n; i += len) {
      int w = 1;
      for (int j = 0; j < len / 2; j++) {
        int u = a[i + j], v = (int)((a[i + j + len / 2] * 1LL * w) % mod);
        a[i + j] = u + v < mod ? u + v : u + v - mod;
        a[i + j + len / 2] = u - v >= 0 ? u - v : u - v + mod;
        w = (int)((w * 1LL * wlen) % mod);
      }
    }
  }
  if (invert) {
    int n_1 = power(n, mod - 2, mod);
    for (int &x : a) x = (int)(x * 1LL * n_1 % mod);
  }
}
void multiply(vector<int> const &a, vector<int> const &b, vector<int> &res) {
  vector<int> fa(a.begin(), a.end()), fb(b.begin(), b.end());
  int n = 1;
  while (n < a.size() + b.size()) n <<= 1;
  fa.resize(n);
  fb.resize(n);
  fft(fa, false);
  fft(fb, false);
  for (int i = 0; i < n; i++) {
    fa[i] = (int)((fa[i] * 1LL * fb[i]) % mod);
  }
  fft(fa, true);
  res.resize(a.size() + b.size() - 1);
  for (int i = 0; i < res.size(); ++i) {
    res[i] = fa[i];
  }
}
vector<int> power(vector<int> &v, long long n) {
  vector<int> vec = {1};
  while (n) {
    if (n & 1) {
      multiply(vec, v, vec);
    }
    n >>= 1;
    multiply(v, v, v);
  }
  return vec;
}
int32_t main() {
  ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
  ;
  int n, k;
  cin >> n >> k;
  vector<int> v(10);
  for (int i = 0; i < k; i++) {
    long long x;
    cin >> x;
    v[x] = 1;
  }
  vector<int> vec = power(v, n / 2);
  long long ans = 0;
  for (int i = 0; i < vec.size(); i++) {
    ans += 1LL * vec[i] * vec[i];
    MOD(&ans);
  }
  cout << ans;
  return 0;
}
