#include <bits/stdc++.h>
using namespace std;
const int maxn = 4e6 + 10, mod = 998244353, inf = 1e9 + 10;
int dp[maxn], ifac[maxn], fac[maxn], inum[maxn];
int Pow(int a, int b) {
  int ans = 1;
  for (; b; b >>= 1, a = 1ll * a * a % mod)
    if (b & 1) ans = 1ll * ans * a % mod;
  return ans;
}
int C(int n, int k) {
  if (n < k) return 0;
  return 1ll * fac[n] * ifac[k] % mod * ifac[n - k] % mod;
}
int IC(int n, int k) {
  if (n < k) return 0;
  return 1ll * ifac[n] * fac[k] % mod * fac[n - k] % mod;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie();
  fac[0] = 1;
  for (int i = 1; i < maxn; i++) fac[i] = 1ll * i * fac[i - 1] % mod;
  ifac[maxn - 1] = Pow(fac[maxn - 1], mod - 2);
  for (int i = maxn - 2; i >= 0; i--)
    ifac[i] = 1ll * ifac[i + 1] * (i + 1) % mod;
  for (int i = 1; i < maxn; i++) inum[i] = 1ll * ifac[i] * fac[i - 1] % mod;
  int n, m;
  cin >> n >> m;
  int sm = 0;
  for (int i = 1; i <= n; i++) {
    dp[i] = (sm + C(i + m, i)) % mod;
    sm = (1ll * sm + 1ll * dp[i] * m % mod * inum[i]) % mod;
    dp[i] = 1ll * dp[i] * IC(i + m - 1, m) % mod;
  }
  return cout << 1ll * dp[n] * (n + m + 1) % mod * Pow(m + 1, mod - 2) % mod
              << endl,
         0;
}
