#include<bits/stdc++.h>

#define endl "\n"
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;

constexpr int N = 2e5 + 5;
constexpr int mod = 998244353;

int n, m;
int ans = 0;
int fact[N], rfact[N];

int sum(ll a, ll b) {
  return (a + b) % mod;
}

int mul(ll a, ll b) {
  return (a * b) % mod;
}

int binpow(int v, int deg) {
  int cur = 1;
  while(deg) {
    if (deg & 1)
      cur = mul(cur, v);
    v = mul(v, v);
    deg >>= 1;
  }
  return cur;
}

int C(int i, int j) {
  return mul(fact[i], mul(rfact[i - j], rfact[j]));
}

void Solve() {
  cin >> n >> m;
  fact[0] = 1;
  for (int i = 1; i <= m; i++)
    fact[i] = mul(fact[i - 1], i);
  rfact[m] = binpow(fact[m], mod - 2);
  for (int i = m - 1; i >= 0; i--)
    rfact[i] = mul(rfact[i + 1], i + 1);
  for (int i = 2; i < n; i++) {
    for (int j = max(i, n - 1); j <= m; j++)
      ans = sum(ans, mul(C(j - 1, i - 1), C(j - i, n - i - 1)));
  }
  cout << ans;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  //auto start = chrono::high_resolution_clock::now();
  Solve();
  //auto end = chrono::high_resolution_clock::now();
  //cout << endl << (chrono::duration_cast<chrono::duration<double>>(end - start)).count();
  return 0;
}