#include<iostream>
using namespace std;
const long mod=998244353;
long power(long a,long b){return b?power(a*a%mod,b/2)*(b%2?a:1)%mod:1;}
long fac[1<<17],inv[1<<17];
long comb(int a,int b){return fac[a]*inv[a-b]%mod*inv[b]%mod;}
main()
{
	int N,K;cin>>N>>K;
	fac[0]=1;
	for(int i=1;i<=K;i++)fac[i]=fac[i-1]*i%mod;
	inv[K]=power(fac[K],mod-2);
	for(int i=K;i--;)inv[i]=inv[i+1]*(i+1)%mod;
	long ans=0,T=1;
	for(int i=1;i<K;i++)
	{
		ans+=comb(K,i)*power(K-i,N)%mod*T%mod;
		T=T*(mod-2)%mod;
	}
	cout<<ans%mod<<endl;
}