#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define rep(i,n) for(int i=0;i<n;i++)
#define riano_ std::ios::sync_with_stdio(false);std::cin.tie(nullptr)

const ll mod = 998244353;
template<uint64_t mod>
struct modint{
    uint64_t val;
    constexpr modint(const int64_t val_=0) noexcept:val((val_%int64_t(mod)+int64_t(mod))%int64_t(mod)){}
    constexpr modint operator-() const noexcept{
        return modint(*this)=mod-val;
    }
    constexpr modint operator+(const modint rhs) const noexcept{
        return modint(*this)+=rhs;
    }
    constexpr modint operator-(const modint rhs) const noexcept{
        return modint(*this)-=rhs;
    }
    constexpr modint operator*(const modint rhs) const noexcept{
        return modint(*this)*=rhs;
    }
    constexpr modint operator/(const modint rhs) const noexcept{
        return modint(*this)/=rhs;
    }
    constexpr modint &operator+=(const modint rhs) noexcept{
        val+=rhs.val;
        val-=((val>=mod)?mod:0);
        return (*this);
    }
    constexpr modint &operator-=(const modint rhs) noexcept{
        val+=((val<rhs.val)?mod:0);
        val-=rhs.val;
        return (*this);
    }
    constexpr modint &operator*=(const modint rhs) noexcept{
        val=val*rhs.val%mod;
        return (*this);
    }
    constexpr modint &operator/=(modint rhs) noexcept{
        uint64_t ex=mod-2;
        modint now=1;
        while(ex){
            now*=((ex&1)?rhs:1);
            rhs*=rhs,ex>>=1;
        }
        return (*this)*=now;
    }
    modint & operator++(){
        val++;
        if (val == mod) val = 0;
        return *this;
    }
    modint operator++(int){
        modint<mod> res = *this;
        ++*this;
        return res;
    }
    constexpr bool operator==(const modint rhs) noexcept{
        return val==rhs.val;
    }
    constexpr bool operator!=(const modint rhs) noexcept{
        return val!=rhs.val;
    }
    friend constexpr ostream &operator<<(ostream& os,const modint x) noexcept{
        return os<<(x.val);
    }
    friend constexpr istream &operator>>(istream& is,modint& x) noexcept{
        uint64_t t;
        is>>t,x=t;
        return is;
    }
};
typedef modint<mod> mint;

mint modinv(long long a, long long m = mod) {
    long long b = m, u = 1, v = 0;
    while (b) {
        long long t = a / b;
        a -= t * b; swap(a, b);
        u -= t * v; swap(u, v);
    }
    u %= m;
    return mint(u);
}

//Combination
vector<ll> fact;
vector<ll> invf;
ll comb(ll n,ll k){
    if(n<0||k<0||k>n) return 0LL;
    else{
        ll a = fact[n]*invf[k]%mod;
        a = a*invf[n-k]%mod;
        return a;
    }
}

int main() {
    riano_; mint ans = 0;
    ll N,K; cin >> N >> K;
    
    fact.assign(N+1,1LL);
    invf.assign(N+1,1LL);
    rep(i,N) fact[i+1] = fact[i]*(i+1)%mod;
    rep(i,N+1) invf[i] = modinv(fact[i],mod).val;
    
    if(K==0){
        cout << 1 << endl; return 0;
    }
    if(K==1){
        if(N%2==0){
            cout << 2 << endl;
        }
        else{
            cout << N-2 << endl;
        }
        return 0;
    }
    ll M = ((N-K)/2)*2;
    for(int i=0;i<=M;i+=2){
        ans += mint(i+1)*mint(comb(N-2-i,K-2));
    }
    cout << ans << endl;
}