#include <stdio.h>
const int p(998244353);
int n, f[10000001], g[10000001];
int abs(const int x) { return x > 0 ? x : -x; }
int comb(const int n, const int m) { return (long long)f[n] * g[m] % p * g[n - m] % p; }
int calc(const int a, const int b, int c, const bool d)
{
	if (!d)
	{
		c = (a << 1) - c;
		if (abs(c) > n) return 0;
		int w(comb(n, (n + abs(c)) >> 1));
		return (w - calc((a << 1) - b, a, c, 0) + p) % p;
	}
	else
	{
		c = (b << 1) - c;
		if (abs(c) > n) return 0;
		int w(comb(n, (n + abs(c)) >> 1));
		return (w - calc(b, (b << 1) - a, c, 1) + p) % p;
	}
}

int main()
{
	int m, w(0); scanf("%d%d", &n, &m); m = (m + 1) >> 1;
	f[0] = f[1] = g[0] = g[1] = 1;
	for (int i(2); i <= n; ++i)
	{
		f[i] = (long long)f[i - 1] * i % p;
		g[i] = (long long)(p - p / i) * g[p % i] % p;
	}
	for (int i(2); i <= n; ++i) g[i] = (long long)g[i - 1] * g[i] % p;
	--n;
	for (int i(-1); i < m; ++i) if ((i & 1) == (n & 1))
		w = ((w + comb(n, (n + abs(i)) >> 1) - calc(m, -2, i, 0) - calc(m, -2, i, 1)) % p + p) % p;
	return !printf("%d\n", w);
}