#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
int main(){
  int N, M;
  cin >> N >> M;
  vector<long long> inv(M * 2);
  inv[1] = 1;
  for (int i = 2; i < M * 2; i++){
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
  }
  vector<long long> fact(M * 2);
  vector<long long> finv(M * 2);
  fact[0] = 1;
  finv[0] = 1;
  for (int i = 1; i < M * 2; i++){
    fact[i] = fact[i - 1] * i % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
  long long ans = 0;
  for (int i = 1; i <= M; i++){
    if (2 * (i - 1) >= N - 1){
      ans += fact[2 * (i - 1)] * finv[N - 1] % MOD * finv[2 * i - N - 1] % MOD;
    }
  }
  ans %= MOD;
  cout << ans << endl;
}