#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#include <atcoder/all>
using ull = unsigned long long;
using namespace std;
using namespace atcoder;
using vst = vector<string>;
using ll = long long;
using ld = long double;
using P = pair<ll,ll>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vP = vector<P>;
#define rep(i, n) for (ll i = 0; i < n; i++)
#define repp(i,k,n) for (ll i = k; i < n; i++)
#define per(i,s,e) for(ll i = s; i >= e; i--)
#define all(v) v.begin(),v.end()
#define yesno(a) a ? cout << "Yes" << '\n' : cout << "No" << '\n'
#define YESNO(a) a ? cout << "YES" << '\n' : cout << "NO" << '\n'
#define UNOmap unordered_map
#define UNOset unordered_set
#define chmax(a,b) a=max(a,b)
#define chmin(a,b) a=min(a,b)
#define debug(x) cerr << #x << " = " << x << '\n'

template<class... T>void in(T&... a){(cin >> ... >> a);}
template<class T, class... Ts>void out(const T& a, const Ts&... b){cout << a;((cout << ' ' <<  b), ...);cout << '\n';}
template<class T> void vin2(vector<T> &u,vector<T> &v){for(ll i = 0; i < (ll)v.size(); i++) in(u[i],v[i]);}
template<class T> void vin(vector<T> &v){for(ll i = 0; i < (ll)v.size(); i++)in(v[i]);}
template<class T> void vout(vector<T> &v){for(ll i = 0; i < (ll)v.size(); i++) cout << v[i] << ' ';cout << "\n";}

ll INF = 1152921504606846976;ll MOD =998244353; ll MOD1 =1000000007;
/* INF = 1 << 60 */

#define sl(...) ll __VA_ARGS__; in(__VA_ARGS__)
 
using mint = modint998244353;
using mint1 = modint1000000007;
using mintn = modint;
using vm = vector<mint>;
using vvm = vector<vm>;

vl dx = {0,0,1,-1}, dy = {1,-1,0,0};
//----------------------------------------------

const int MAX = 510000;
mint fac[MAX], finv[MAX], inv[MAX];

// テーブルを作る前処理
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i;
        inv[i] = MOD - inv[MOD%i] * (MOD / i);
        finv[i] = finv[i - 1] * inv[i];
    }
}

// 二項係数計算
mint COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * finv[k] * finv[n - k];
}

int main(){
  ios::sync_with_stdio(false);cin.tie(nullptr);cout<<fixed<<setprecision(15);
//==============================================
  
  COMinit();
  // out(COM(30,2).val());
  
  ll N,K;
  in(N,K);
  mint ans = 0;
  rep(i,100009){
    if(N-K*i+i <= 0) break;
    ans += COM(N-K*i+i,i);
    // out(N-K*i,i);
  }
  out(ans.val());
}