#include<bits/stdc++.h>
using namespace std;
#ifdef LOCAL
 #define debug(...) fprintf(stdout, ##__VA_ARGS__)
 #define debag(...) fprintf(stderr, ##__VA_ARGS__)
#else
 #define debug(...) void(0)
 #define debag(...) void(0)
#endif
#define int long long
inline int read(){int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;
ch=getchar();}while(ch>='0'&&ch<='9'){x=(x<<1)+
(x<<3)+(ch^48);ch=getchar();}return x*f;}
#define Z(x) (x)*(x)
#define pb push_back
#define fi first
#define se second
//#define M
#define mo 998244353
#define N 1000010
int pw(int a, int b) {
	int ans = 1; 
	while(b) {
		if(b & 1) ans *= a; 
		a *= a; b >>= 1; 
		ans %= mo; a %= mo; 
	}
	return ans; 
}
int pw(int a) { return pw(a, mo - 2); }
int fac[N], inv[N], ifac[N]; 
void init(int n) {
	int i; 
	for(i = fac[0] = 1; i <= n; ++i) fac[i] = fac[i-1] * i % mo; 
	ifac[n] = pw(fac[n], mo-2); 
	for(i = n - 1; i >= 0; --i) ifac[i] = ifac[i+1] * (i+1) % mo; 
    for(i = 1; i <= n; ++i) inv[i] = ifac[i] * fac[i-1] % mo; 
}
int C(int n, int m) {
	if(m > n) return 0;
	return fac[n] * ifac[m] % mo * ifac[n - m] % mo; 
}
inline void Mod(int &a) { if(a >= mo || a <= -mo) a %= mo; if(a < 0) a += mo; }
inline void Add(int &a, int b) { a += b; Mod(a); }
inline void Mul(int &a, int b) { Mod(b); a *= b; Mod(a); } 
const int iv2 = pw(2, mo - 2); 
int n, m, i, j, k, T;
int ans, o; 

int F(int n, int m) {
	if(m == 0) return 1; 
	int k = Z(C(n + m, m)) % mo - C(n + m, m - 1) * C(n + m, m + 1) % mo; 
	Mod(k); debug("[%lld %lld] %lld\n", n, m, k); 
	return Mod(k), k; 
}

signed main()
{
	#ifdef LOCAL
	  freopen("in.txt", "r", stdin);
	  freopen("out.txt", "w", stdout);
	#endif
//	srand(time(NULL));
//	T = read();
//	while(T--) {
//
//	}
	n = read(); m = read(); init(N - 1); 
	for(i = 0, o = 1; i <= min(n, m); ++i, o = -o) {
		Add(ans, o * F(n, m - i) * C(n, i) % mo); 
	}
	printf("%lld", ans); 
	return 0;
}