#include <bits/stdc++.h>
using namespace std;
const long long mod = 998244353;
long long a[1 << 20], t[1 << 20];
long long p(long long a, long long b) {
  long long ans = 1;
  for (; b; b >>= 1, a = a * a % mod)
    if (b & 1) ans = ans * a % mod;
  return ans;
}
long long w[1 << 20];
int rev(int x, int n) {
  int ret = 0;
  for (int i = 0; i < n; i++) ret += ((x >> i) & 1) << n - i - 1;
  return ret;
}
void fft(long long ar[], int n, bool inv = 0) {
  int N = 1 << n, m = N - 1, i, j, k;
  w[0] = 1;
  w[1] = p(3, mod >> n);
  for (i = 2; i < N; i++) w[i] = w[i - 1] * w[1] % mod;
  if (inv)
    for (i = 1; i < N >> 1; i++) swap(w[i], w[N - i]);
  for (i = 0; i < N; i++) t[rev(i, n)] = ar[i];
  memcpy(ar, t, sizeof(ar[0]) << n);
  long long sc = N >> 1;
  for (i = 0; i < n; i++, sc >>= 1) {
    for (j = 0; j < N; j++) {
      if (j & (1 << i)) continue;
      k = j | (1 << i);
      long long aa = (ar[j] + ar[k] * w[(sc * j) & m]) % mod;
      long long bb = (ar[j] + ar[k] * w[(sc * k) & m]) % mod;
      ar[j] = aa;
      ar[k] = bb;
    }
  }
  long long q = p(N, mod - 2);
  if (inv)
    for (i = 0; i < N; i++) ar[i] = ar[i] * q % mod;
}
int main() {
  int n, k, i, x;
  scanf("%d%d", &n, &k);
  for (i = 0; i < k; i++) scanf("%d", &x), a[x] = 1;
  fft(a, 20, 0);
  for (i = 0; i < 1 << 20; i++) a[i] = p(a[i], n / 2);
  fft(a, 20, 1);
  long long ans = 0;
  for (i = 0; i < 1 << 20; i++) ans = (ans + a[i] * a[i]) % mod;
  printf("%lld", ans);
}
