#include <vector>
#include <algorithm>
#include <cstdio>
using namespace std;

int main(){
	int n,m;
	scanf("%d%d",&n,&m);
	vector<int>x(m);
	for(int i=0;i<m;i++)scanf("%d",&x[i]);
	vector<int>bag(n);
	vector<int>Ma={168647939,592951213};
	vector<int>R;
	for(auto &M: Ma){
		bag[0]=1;
		for(int i=1;i<n;i++)bag[i]=0;
		for(int i=1;i<n;i++){
			for(auto &e: x)if(e<=i)bag[i]=(bag[i]+bag[i-e])%M;
		}
		R.push_back(bag[n-1]);
	}
	long long Rm=(R[1]-R[0]+Ma[1])*442445312LL%Ma[1];
	printf("%lld\n",Rm*Ma[0]+R[0]);
}