#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2000000, MOD = 998244353;
long long inv[MAXN], fac[MAXN];
int c(int n,int m) {//计算组合数
    return n < m ? 0 : 1ll * fac[n] * inv[m] % MOD * inv[n - m] % MOD;
}
void init() {//预处理组合数
    inv[1] = inv[0] = fac[1] = fac[0] = 1;
    for (int i = 2; i < MAXN; i++) {
        fac[i] = (fac[i - 1] % MOD * i % MOD) % MOD;
        inv[i] = ((MOD - MOD / i) * inv[MOD % i] % MOD) % MOD;
    }
    for (int i = 2; i < MAXN; i++) inv[i] = (inv[i - 1] % MOD * inv[i] % MOD) % MOD;
}
int main() {
    freopen("ball.in","r",stdin);
    freopen("ball.out","w",stdout);
    long long n, m;
    cin >> n >> m;
    init();
    long long ans = 0;
    for (int i = 1; i < n; i++) {//计算
        ans += 1ll * c(n - 1, i - 1) * c(m + n - i - 1, n - i - 1) % MOD * c(n, i) % MOD;
        ans%=MOD;
    }
    if (m == 0) ans++;//注意
    cout << ans << endl;
    return 0;
}