#include <bits/stdc++.h>
using namespace std;
const int Maxn = 200010, Maxk = 12;
const int inf = 2147483647;
const int mod = 998244353, gn = 3;
int read() {
  int x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9')
    x = (x << 3) + (x << 1) + (ch ^ 48), ch = getchar();
  return x * f;
}
int Pow(int x, int y) {
  if (!y) return 1;
  int t = Pow(x, y >> 1), re = (long long)t * t % mod;
  if (y & 1) re = (long long)re * x % mod;
  return re;
}
int rev[Maxn * 14];
void ntt(int *a, int n, int op) {
  for (int i = 0; i < n; i++)
    if (i < rev[i]) swap(a[i], a[rev[i]]);
  for (int i = 1; i < n; i <<= 1) {
    int wn;
    if (op == 1)
      wn = Pow(gn, (mod - 1) / (i << 1));
    else
      wn = Pow(gn, mod - 1 - (mod - 1) / (i << 1));
    for (int j = 0; j < n; j += (i << 1)) {
      int w = 1;
      for (int k = 0; k < i; k++) {
        int t = (long long)a[i + j + k] * w % mod;
        w = (long long)w * wn % mod;
        a[i + j + k] = (a[j + k] - t + mod) % mod;
        a[j + k] = (a[j + k] + t) % mod;
      }
    }
  }
  if (op == -1) {
    int inv = Pow(n, mod - 2);
    for (int i = 0; i < n; i++) a[i] = (long long)a[i] * inv % mod;
  }
}
int n, k, g[Maxn * 14], f[Maxn * 14];
void f_Pow() {
  int m = n >> 1;
  bool fir = true;
  int N = 1;
  while (N <= m * 9) N <<= 1;
  rev[0] = 0;
  for (int i = 1; i < N; i++)
    rev[i] = ((rev[i >> 1] >> 1) | ((i & 1) * (N >> 1)));
  ntt(g, N, 1);
  while (m) {
    if (m & 1) {
      if (fir) {
        fir = false;
        for (int i = 0; i < N; i++) f[i] = g[i];
      } else {
        for (int i = 0; i < N; i++) f[i] = (long long)f[i] * g[i] % mod;
      }
    }
    for (int i = 0; i < N; i++) g[i] = (long long)g[i] * g[i] % mod;
    m >>= 1;
  }
  ntt(f, N, -1);
}
int main() {
  memset(g, 0, sizeof(g));
  n = read(), k = read();
  for (int i = 1; i <= k; i++) g[read()] = 1;
  f_Pow();
  int ans = 0;
  for (int i = 0; i <= (n >> 1) * 9; i++)
    ans = (ans + (long long)f[i] * f[i] % mod) % mod;
  printf("%d", ans);
}
