#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;

typedef modint998244353 mint;
typedef long long ll;

#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)
#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)

template <typename T> bool chmin(T &a, const T &b) {
	if (a <= b) return false;
	a = b;
	return true;
}
template <typename T> bool chmax(T &a, const T &b) {
	if (a >= b) return false;
	a = b;
	return true;
}

//defmodfact
const int COMinitMAX = 998244;
mint fact[COMinitMAX+1], factinv[COMinitMAX+1];

void modfact(){
	fact[0] = 1;
	for (int i=1; i<=COMinitMAX; i++){
		fact[i] = fact[i-1] * i;
	}
	factinv[COMinitMAX] = fact[COMinitMAX].inv();
	for (int i=COMinitMAX-1; i>=0; i--){
		factinv[i] = factinv[i+1] * (i+1);
	}
}

mint cmb(int a, int b){
	if (a<b || b<0) return mint(0);
	return fact[a]*factinv[b]*factinv[a-b];
}
//--------


int main(){
	modfact();
	int n, k; cin >> n >> k;

	if (n == 1){
		if (k == 1  || k == 6 || k == 5){
			cout << 1 << endl;
		}else if (k == 2 || k == 4){
			cout << 3 << endl;
		}else{
			cout << 3 << endl;
		}
		return 0;
	}

	mint ans = 0;
	// none
	ans += cmb(2*n+4, k);

	if (n % 2 == 0){
		if (k % 2 == 0){
			ans += cmb(n+2, k/2);
		}
	}else{
		if (k % 2 == 0){
			ans += cmb(n-1+2, k/2);
			ans += cmb(n-1+2, (k-2)/2);
		}else{
			ans += cmb(n-1+2, (k-1)/2) * 2;
		}
	}

	if (k % 2 == 0){
		ans += cmb(n+2, k/2) * 2;
	}

	ans *= mint(4).inv();
	cout << ans.val() << endl;
}