#include "iostream"
#include "cstring"
#include "cstdio"
#include "algorithm"
#include "queue"
#include "vector"
#include "queue"
#include "stack"
#include "ctime"
#include "set"
#include "map"
#include "cmath"
using namespace std;
#define fi first
#define se second
#define vi vector<int>
#define pb push_back
#define eb emplace_back
#define pii pair<int,int>
#define mp make_pair
#define rep( i , a , b ) for( int i = (a) , i##end = b ; i <= i##end ; ++ i )
#define per( i , a , b ) for( int i = (a) , i##end = b ; i >= i##end ; -- i )
#define mem( a ) memset( a , 0 , sizeof (a) )
#define all( x ) x.begin() , x.end()
//#define int long long
typedef long long ll;
const int MAXN = 5e5 + 10;
const int P = 998244353;
int n , m;
int v[MAXN];

int Pow( int x , int a ) {
	int ret = 1;
	while( a ) {
		if( a & 1 ) ret = ret * 1ll * x % P;
		x = x * 1ll * x % P , a >>= 1;
	}
	return ret;
}

int Wn[2][MAXN];
void getwn( int len ) {
	for( int mid = 1 ; mid < len ; mid <<= 1 ) {
		int w0 = Pow( 3 , ( P - 1 ) / ( mid << 1 ) ) , w1 = Pow( 3 , P - 1 - ( P - 1 ) / ( mid << 1 ) );
		Wn[0][mid] = Wn[1][mid] = 1;
		for( int i = 1 ; i < mid ; ++ i )
			Wn[0][mid + i] = Wn[0][mid + i - 1] * 1ll * w0 % P,
			Wn[1][mid + i] = Wn[1][mid + i - 1] * 1ll * w1 % P;
	}
}
int rev[MAXN];
void getr( int len ) {
	int l = __builtin_ctz( len ) - 1;
	for( int i = 1 ; i < len ; ++ i ) rev[i] = ( rev[i >> 1] >> 1 ) | ( ( i & 1 ) << l );
}
void NTT( vi& A , int len , int typ ) {
	for( int i = 0 ; i < len ; ++ i ) if( i < rev[i] ) swap( A[i] , A[rev[i]] );
	for( int mid = 1 ; mid < len ; mid <<= 1 )
		for( int i = 0 ; i < len ; i += ( mid << 1 ) )
			for( int j = i ; j < i + mid ; ++ j ) {
				int t0 = A[j] , t1 = A[j + mid] * 1ll * Wn[typ][j - i + mid] % P;
				A[j] = ( t0 + t1 > P ? t0 + t1 - P : t0 + t1 ) , A[j + mid] = ( t0 < t1 ? t0 - t1 + P : t0 - t1 );
			}
	if( typ ) for( int i = 0 , iv = Pow( len , P - 2 ) ; i < len ; ++ i ) A[i] = A[i] * 1ll * iv % P;
}
void NTT( int A[] , int len , int typ ) {
	for( int i = 0 ; i < len ; ++ i ) if( i < rev[i] ) swap( A[i] , A[rev[i]] );
	for( int mid = 1 ; mid < len ; mid <<= 1 )
		for( int i = 0 ; i < len ; i += ( mid << 1 ) )
			for( int j = i ; j < i + mid ; ++ j ) {
				int t0 = A[j] , t1 = A[j + mid] * 1ll * Wn[typ][j - i + mid] % P;
				A[j] = ( t0 + t1 > P ? t0 + t1 - P : t0 + t1 ) , A[j + mid] = ( t0 < t1 ? t0 - t1 + P : t0 - t1 );
			}
	if( typ ) for( int i = 0 , iv = Pow( len , P - 2 ) ; i < len ; ++ i ) A[i] = A[i] * 1ll * iv % P;
}
vi mul( vi A , vi B , int flg = 0 ) {
	if( A.empty() || B.empty() ) return vector<int> ();
	int S = A.size() + B.size() , len = 1;
	while( len <= S ) len <<= 1;
	getr( len );
	A.resize( len ) , B.resize( len );
	NTT( A , len , 0 ) , NTT( B , len , 0 );
	rep( i , 0 , len - 1 ) A[i] = A[i] * 1ll * B[i] % P;
	NTT( A , len , 1 );
	while( A.size() && A.back() == 0 ) A.pop_back();
	return A;
}

//template<typename T>
//T&& add( T&& A , T&& B ) {
//	if( A.size() > B.size() ) {
//		rep( i , 0 , B.size() - 1 ) A[i] += B[i];
//		return forward<T>( A );
//	} else {
//		rep( i , 0 , A.size() - 1 ) B[i] += A[i];
//		return forward<T>( B ); 
//	}
//}

vi add( vi A , vi B ) {
	if( A.size() > B.size() ) {
		rep( i , 0 , B.size() - 1 ) A[i] += B[i];
		return A;
	} else {
		rep( i , 0 , A.size() - 1 ) B[i] += A[i];
		return B;
	}
}

const int N = 3;
struct mtrx {
	vi A[3][3];
	mtrx operator * ( mtrx B ) {
		mtrx res;
		rep( i , 0 , N - 1 ) rep( j , 0 , N - 1 ) rep( k , 0 , N - 1 ) 
			res.A[i][j] = add( move( res.A[i][j] ) , mul( A[i][k] , B.A[k][j] ) );
		return res;
	}
	void init( int i ) {
		if( i <= 16 ) {
			A[0][0] = { 1 , -v[i] };
			A[1][0] = { 1 };
			A[2][1] = { 1 };
		} else if( i <= 65537 ) {
			A[0][0] = { 1 } , A[0][1] = { 0 , -v[i] };
			A[1][0] = { 1 };
			A[2][1] = { 1 };
		} else {
			A[0][0] = { 1 } , A[0][2] = { 0 , -v[i] };
			A[1][0] = { 1 } , A[2][1] = { 1 };
		}
	}
} A[MAXN] ;

mtrx mul( int l , int r ) {
	if( l == r ) 
		return A[l];
	int m = ( l + r >> 1 );
	return mul( l , m ) * mul( m + 1 , r );
}

int tmpa[MAXN];
void Inv( vi A , int B[] , int n ) { // B = inv A
	if( n == 1 ) return void( B[0] = Pow( A[0] , P - 2 ) );
	Inv( A , B , n + 1 >> 1 );
	int len = 1;
	while( len <= n + n ) len <<= 1;
	getr( len );
	for( int i = 0 ; i < n ; ++ i ) tmpa[i] = A[i];
	for( int i = n ; i < len ; ++ i ) tmpa[i] = 0;
	NTT( tmpa , len , 0 ) , NTT( B , len , 0 );
	rep( i , 0 , len - 1 ) B[i] = B[i] * ( 2 - tmpa[i] * 1ll * B[i] % P + P ) % P;
	NTT( B , len , 1 );
	rep( i , n , len - 1 ) B[i] = 0;
}

int as[MAXN];

void solve() {
	cin >> n >> m;
	rep( i , 1 , m ) scanf("%d",v + i) , A[i].init( i );
	mtrx pr;
	pr.A[0][0] = { 1 };
	mtrx res = mul( 1 , m ) * pr;
	vi re = res.A[0][0];
//	for( int x : re ) cout << x << endl;
	Inv( re , as , n + 1 );
	cout << as[n] << endl;
}

signed main() {
	getwn( 1 << 18 );
//	freopen("in","r",stdin);
//	freopen("out","w",stdout);
//	int T;cin >> T;while( T-- ) solve();
	solve();
}