#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#define _USE_MATH_DEFINES
#include<iostream>
#include<vector>
#include<algorithm>
#include<cmath>
#include<string>
#include<iomanip>
#include<numeric>
#include<queue>
#include<deque>
#include<stack>
#include<set>
#include<map>
#include<random>
#include<bitset>
#include<cassert>
#include<complex>
#include<fstream>
#include<cstdlib>
using namespace std;
typedef long long ll;
const int mod=998244353;
const int dx[]={1,0,0,-1},dy[]={0,1,-1,0};
bool flg[100001];
int dp[100001];
int main(){
	int k,n,x;
	cin>>k>>n;
	while(cin>>x)
		flg[x]=1;
	dp[0]=1;
	for(int i=0;i<k;i++){
		int tmp=dp[i];
		for(int j=1;j<=k-i;j++){
			dp[i+j]+=tmp*flg[j];
			dp[i+j]-=mod*(dp[i+j]>=mod);
		}
	}
	cout<<dp[k]<<endl;
}