#include <bits/stdc++.h>
using namespace std;
const int N = 1000005, mod = 998244353;
int n, ni, G, Gi, k, m, rd, ans;
int a[4 * N], rev[4 * N];
void exGCD(int a, int b, int &x, int &y) {
  if (!b) {
    x = 1, y = 0;
    return;
  }
  exGCD(b, a % b, y, x), y -= a / b * x;
}
int Qpow(int x, int k) {
  if (!k) return 1;
  if (k == 1) return x;
  int tmp = Qpow(x, k / 2);
  return k % 2 ? 1ll * tmp * tmp % mod * x % mod : 1ll * tmp * tmp % mod;
}
int Inv(int x) {
  int xx, yy;
  exGCD(x, mod, xx, yy);
  return (xx % mod + mod) % mod;
}
void NTT(int *arr, int len, int typ) {
  for (int i = 0; i <= len; i++)
    if (rev[i] > i) swap(arr[rev[i]], arr[i]);
  for (int i = 2; i <= len; i <<= 1) {
    int lth = i >> 1, ort = Qpow(~typ ? G : Gi, (mod - 1) / i);
    for (int j = 0; j < len; j += i) {
      int ori = 1, tmp;
      for (int k = j; k < j + lth; k++, ori = 1ll * ori * ort % mod) {
        tmp = 1ll * ori * arr[k + lth] % mod;
        arr[k + lth] = (arr[k] - tmp + mod) % mod;
        arr[k] = (arr[k] + tmp) % mod;
      }
    }
  }
  if (typ == -1) {
    int ni = Inv(len);
    for (int i = 0; i <= len; i++) arr[i] = 1ll * arr[i] * ni % mod;
  }
}
void Init() {
  scanf("%d%d", &n, &k);
  G = 3, Gi = Inv(G), m = 1;
  for (int i = 1; i <= k; i++) scanf("%d", &rd), a[rd]++;
  while (m <= n * 5) m <<= 1;
  for (int i = 1; i <= m; i++) rev[i] = (rev[i >> 1] >> 1) + (i & 1) * (m >> 1);
}
int main() {
  Init();
  NTT(a, m, 1);
  for (int i = 0; i <= m; i++) a[i] = Qpow(a[i], n / 2);
  NTT(a, m, -1);
  for (int i = 0; i <= m; i++) ans += 1ll * a[i] * a[i] % mod, ans %= mod;
  printf("%d", ans);
  return 0;
}
