#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define rep2(i, s, n) for (int i = (s); i < (int)(n); i++)
#define rrep2(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)
#define sz(x) (int)((x).size())
#define ALL(x) (x).begin(), (x).end()
using ll = long long; using vi = vector<int>; using vvi = vector<vi>; using vl = vector<long long>; using vvl = vector<vl>; using vs = vector<string>;
const int inf = 1073741823;/*2^30-1*/ const ll infl = 1LL << 60;

void ansYN(bool ok) { cout << (ok ? "Yes" : "No") << endl; }
bool isKaibun(string str) { string str2 = str;reverse(str.begin(), str.end());return str == str2; }
//memo double型: printf("%.10f\n",ans);   long double型: printf("%.10Lf\n", ans);
long long fastPow(long long x, long long n, long long MOD) { long long ans = 1;while (n > 0) { if (n & 1) { ans *= x;ans %= MOD; }x *= x;x %= MOD;n >>= 1; }return ans; }
long long modinv(long long A, long long MOD) { return fastPow(A, MOD - 2, MOD); }
long long modDiv(long long A, long long B, long long MOD) { return (A * modinv(B, MOD)) % MOD; }

template<typename T1, typename T2>istream& operator>>(istream& is, pair<T1, T2>& p) { return is >> p.first >> p.second; }
template<typename T1, typename T2>ostream& operator<<(ostream& os, const pair<T1, T2>& p) { return os << p.first << ' ' << p.second; }
template<typename T>istream& operator>>(istream& is, vector<T>& v) { for (auto& x : v) is >> x;return is; }
template<typename T>ostream& operator<<(ostream& os, const vector<T>& v) { for (size_t i = 0; i < v.size(); ++i) { if (i) os << ' ';os << v[i]; }return os; }
struct Point { int x, y;Point() : x(0), y(0) {}Point(int x_, int y_) : x(x_), y(y_) {}Point operator+(const Point& r) const { return { x + r.x, y + r.y }; }Point operator-(const Point& r) const { return { x - r.x, y - r.y }; }Point operator*(int k) const { return { x * k, y * k }; }Point operator/(int k) const { return { x / k, y / k }; }bool operator==(const Point& r) const { return x == r.x && y == r.y; }bool operator!=(const Point& r) const { return !(*this == r); } };
inline long long dot(const Point& a, const Point& b) { return 1LL * a.x * b.x + 1LL * a.y * b.y; }
inline long long cross(const Point& a, const Point& b) { return 1LL * a.x * b.y - 1LL * a.y * b.x; }
inline long long abs2(const Point& a) { return dot(a, a); }
inline istream& operator>>(istream& is, Point& p) { return is >> p.x >> p.y; }inline ostream& operator<<(ostream& os, const Point& p) { return os << p.x << ' ' << p.y; }

const vi dx = { 1, -1, 0, 0 };  const vi dx8 = { 1, 1, 0, -1, -1, -1, 0, 1 };
const vi dy = { 0, 0, 1, -1 };  const vi dy8 = { 0, 1, 1, 1, 0, -1, -1, -1 };

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

ll N,K;
cin >> N >> K;
K = min(K,N-K);

const int mod =  998244353;

ll ans = 1;

rrep2(i,N-K+1,N+1){
ans *= i;
ans %= mod;  
}

ll div = 1;
rep2(i,1,K+1){
div *= i;
div %= mod;  
}

ans = modDiv(ans,div,mod);
cout << ans << endl;

    
    return 0;
}