#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll=long long;
const int mod=998244353;
const int rev=(mod+1)/2;

ll my_pow(ll a,ll b){
    ll res=1;
    while(b){
        if(b&1) res=res*a%mod;
        a=a*a%mod;
        b>>=1;
    }
    return res;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    ll N,K;
    cin>>N>>K;
    ll R=my_pow(N,mod-2);
    cout<<N*((1+(K*R+mod-rev+rev*my_pow(R*(N-2)%mod,K))%mod*rev)%mod)%mod<<"\n";
}