#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll maxn=2000005;
const ll mod=998244353;
ll s[maxn+5],p[maxn+5];
ll qpow(ll a,ll b){
    ll ans,cur;
    ans=1,cur=a;
    while(b){
        if(b&1)ans=ans*cur%mod;
        cur=cur*cur%mod;
        b>>=1;
    }
    return ans;
}
ll inv(ll a){
    return qpow(a,mod-2);
}
void init(){
    ll i;
    s[0]=1;
    for(i=1;i<=maxn;i++)s[i]=s[i-1]*i%mod;
    p[maxn]=inv(s[maxn]);
    for(i=maxn-1;i>=0;i--)p[i]=p[i+1]*(i+1)%mod;
}
ll cal(ll n,ll m){
    ll i,ans,cur;
    if(m<0 or m>n)return 0;
    if(n<=maxn)return s[n]*p[m]%mod*p[n-m]%mod;
    if(m>n/2)m=n-m;
    cur=1,ans=1;
    for(i=1;i<=m;i++){
        cur=cur*((n-i+1)%mod)%mod;
        ans=ans*i%mod;
    }
    return cur*inv(ans)%mod;
}
ll luc(ll n,ll m){
    if(m==0)return 1;
    return luc(n/mod,m/mod)*cal(n%mod,m%mod)%mod;
}
int main(){
    ll n,m;
    init();
    scanf("%lld%lld",&n,&m);
    if(m>n/2)m=n-m;
    printf("%lld\n",luc(n,m));
    return 0;
}