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

using ll = long long;
using VI = vector<int>;
using P = pair<int, int>;

#define REP(i, n) for (int i = 0; i < (int)(n); i++)
#define FOR(i, a, b) for (ll i = a; i < (ll)(b); i++)
#define ALL(a) (a).begin(),(a).end()

constexpr int INF = 1001001001;
constexpr ll LINF = 1001001001001001001ll;
constexpr int DX[] = {1, 0, -1, 0};
constexpr int DY[] = {0, 1, 0, -1};

template< typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true); }
template< typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true); }

const ll MOD = 998244353;

vector<ll> f(200001, 1);

ll mod_pow(ll x, ll n, ll mod) {
    ll res = 1;
    while (n > 0) {
        if (n & 1) res = res * x % mod;
        x = x * x % mod;
        n >>= 1;
    }
    return res;
}

ll C(ll n, ll k) {
    return f[n] * mod_pow(f[k], MOD - 2, MOD) % MOD * mod_pow(f[n - k], MOD - 2, MOD) % MOD;
}

int main() {
    REP(i, 200000) f[i + 1] = f[i] * (i + 1) % MOD;
    ll N, K, ans = 0;
    cin >> N >> K;
    // 1...10x...x01...1
    if (K == 0) {
        cout << 1 << endl;
        return 0;
    }
    if (K == 1) {
        // 01even X = 0, Y = 1
        // 01odd X = 1, Y = 1
        if (N % 2) {
            cout << N - 2 << endl;
        } else {
            cout << 2 << endl;
        }
        return 0;
    }
    for (ll i = 0; i <= N - K; i += 2) {
        ans = (ans + C(N - i - 2, K - 2) * (i + 1)) % MOD;
    }
    cout << ans << endl;
}