#include <bits/stdc++.h>
using namespace std;

using ll = long long;

bool chmin(auto &a, auto b) { return a > b ? a = b, true : false; }
bool chmax(auto &a, auto b) { return a < b ? a = b, true : false; }

#include <atcoder/modint>
using mint = atcoder::modint998244353;

const mint fac_memo[] = {
    1, 808258749, 117153405, 761699708, 573994984, 62402409, 511621808, 242726978, 887890124, 875880304
};

mint fac(int n) {
    int m = n / (int)1e8;
    mint res = fac_memo[m];
    m *= (int)1e8;
    while (m < n) {
        res *= ++m;
    }
    return res;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N, K;
    cin >> N >> K;
    if (N < mint::mod()) {
        cout << (fac(N) * (fac(N - K) * fac(K)).inv()).val() << endl;
    } else {
        if (K < mint::mod() && N - K < mint::mod()) {
            cout << 0 << '\n';
        } else {
            K = min(K, N - K);
            mint a = 1, b = 1;
            for (int i = 0; i < K; i++) {
                a *= N - i;
                b *= i + 1;
            }
            cout << (a / b).val() << endl;
        }
    }
}