#include <bits/stdc++.h>

#define elif else if
#define ll long long
#define vll vector<long long>
#define vec vector
#define embk emplace_back
#define rep(i, n) for (ll i = 0; i < n; i++)
#define rep3(i, n, k) for (ll i = k; i < n; i++)
#define all(a) a.begin(), a.end()
#define YNeos(bool) (bool ? "Yes" : "No")
#define vllin(a, n) vll a(n); rep(i, n) cin >> a[i]
#define vchin(a, n) vec<char> a(n); rep(i, n) cin >> a[i]

using namespace std;
const ll INF = 1LL << 60;
const ll mod = 998244353;
//const ll mod = 1000000007;
const double pi = acos(-1);


#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;



//nCkを高速で 
ll limit = 1000000;
vec<mint> fac(limit), finv(limit), inv(limit);

void nCk_init() {
  fac[0] = 1;
  fac[1] = 1;
  finv[0] = 1;
  finv[1] = 1;
  inv[1] = 1;

  for (int i = 2; i < limit; i++) {
    fac[i] = fac[i - 1] * i;
    inv[i] = mod - inv[mod % i] * (mod / i);
    finv[i] = finv[i - 1] * inv[i];
  }

  return;
}

mint nCk(ll n, ll k) {
  if (n < k) return 0;
  if (n < 0 || k < 0) return 0;

  return fac[n] * finv[k] * finv[n - k];
}


//Main Program
int main() {
  ll n, m; cin >> n >> m;
  
  nCk_init();
  mint ans = 0;

  rep3(i, m+1, 1) {
    ans += nCk(2 * i - 2, n - 1);
  }
  

  cout << ans.val() << endl;

}