/*
Author: QAQAutomaton
Lang: C++
Code: F.cpp
Mail: lk@qaq-am.com
Blog: https://www.qaq-am.com/
*/
#include<bits/stdc++.h>
#define int long long
#define debug(...) fprintf(stderr,__VA_ARGS__)
#define DEBUG printf("Passing [%s] in LINE %d\n",__FUNCTION__,__LINE__)
#define Debug debug("Passing [%s] in LINE %d\n",__FUNCTION__,__LINE__)
#define all(x) x.begin(),x.end()
#define x first
#define y second
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
int inf;
const double eps=1e-8;
const double pi=acos(-1.0);
template<class T,class T2>int chkmin(T &a,T2 b){return a>b?a=b,1:0;}
template<class T,class T2>int chkmax(T &a,T2 b){return a<b?a=b,1:0;}
template<class T>T sqr(T a){return a*a;}
template<class T,class T2>T mmin(T a,T2 b){return a<b?a:b;}
template<class T,class T2>T mmax(T a,T2 b){return a>b?a:b;}
template<class T>T aabs(T a){return a<0?-a:a;}
template<class T>int dcmp(T a,T b){return a>b;}
template<int *a>int cmp_a(int x,int y){return a[x]<a[y];}
#define min mmin
#define max mmax
#define abs aabs
struct __INIT__{
	__INIT__(){
		memset(&inf,0x3f,sizeof(inf));
	}
}__INIT___;
namespace io {
	const int SIZE = (1 << 21) + 1;
	char ibuf[SIZE], *iS, *iT, obuf[SIZE], *oS = obuf, *oT = oS + SIZE - 1, c, qu[55]; int f, qr;
	// getchar
	#define gc() (iS == iT ? (iT = (iS = ibuf) + fread (ibuf, 1, SIZE, stdin), (iS == iT ? EOF : *iS ++)) : *iS ++)
	// print the remaining part
	inline void flush () {
		fwrite (obuf, 1, oS - obuf, stdout);
		oS = obuf;
	}
	// putchar
	inline void putc (char x) {
		*oS ++ = x;
		if (oS == oT) flush ();
	}
	template<typename A>
	inline bool read (A &x) {
		for (f = 1, c = gc(); c < '0' || c > '9'; c = gc()) if (c == '-') f = -1;else if(c==EOF)return 0;
		for (x = 0; c <= '9' && c >= '0'; c = gc()) x = x * 10 + (c & 15); x *= f;
		return 1;
	}
	inline bool read (char &x) {
		while((x=gc())==' '||x=='\n' || x=='\r');
		return x!=EOF;
	}
	inline bool read(char *x){
		while((*x=gc())=='\n' || *x==' '||*x=='\r');
		if(*x==EOF)return 0;
		while(!(*x=='\n'||*x==' '||*x=='\r'||*x==EOF))*(++x)=gc();
		*x=0;
		return 1;
	}
	template<typename A,typename ...B>
	inline bool read(A &x,B &...y){
		return read(x)&&read(y...);
	}
	template<typename A>
	inline bool write (A x) {
		if (!x) putc ('0'); if (x < 0) putc ('-'), x = -x;
		while (x) qu[++ qr] = x % 10 + '0',  x /= 10;
		while (qr) putc (qu[qr --]);
		return 0;
	}
	inline bool write (char x) {
		putc(x);
		return 0;
	}
	inline bool write(const char *x){
		while(*x){putc(*x);++x;}
		return 0;
	}
	inline bool write(char *x){
		while(*x){putc(*x);++x;}
		return 0;
	}
	template<typename A,typename ...B>
	inline bool write(A x,B ...y){
		return write(x)||write(y...);
	}
	//no need to call flush at the end manually!
	struct Flusher_ {~Flusher_(){flush();}}io_flusher_;
}
using io :: read;
using io :: putc;
using io :: write;
int fac[1<<20|5],inv[1<<20|5],invf[1<<20|5],nn;
const int p=998244353,G=114514;
int f[1<<20|5],g[1<<20|5],N,rev[1<<20|5],w[1<<22|5];
int C(int a,int b){return fac[a]*invf[b]%p*invf[a-b]%p;}

int fpm(int a,int b){
	int c=1;for(;b;b>>=1,a=a*a%p)if(b&1)c=c*a%p;
	return c;
}
void upd(int N){
	if(nn<N){
		for(int i=nn;i<N;++i){
			fac[i]=fac[i-1]*i%p;
			inv[i]=(p-p/i)*inv[p%i]%p;
			invf[i]=inv[i]*invf[i-1]%p;
		}	
		for(int i=nn;i<N;i<<=1){
			int xw=fpm(G,(p-1)/i/2),ww=1;
			for(int j=0;j<i;++j){
				w[i+j]=ww;
				ww=ww*xw%p;
			}
		}
		nn=N;
	}
}
int sum(int a,int b){return (a+=b)>=p?a-p:a;}
int minu(int a,int b){return (a-=b)<0?a+p:a;}
void dft(int *a,int N){
	for(int i=1;i<N;++i){
		rev[i]=rev[i>>1]>>1|((i&1)*(N>>1));
		if(i<rev[i])swap(a[i],a[rev[i]]);
	}
	for(int i=1;i<N;i<<=1){
		for(int j=0;j<N;j+=i+i){
			for(int k=0;k<i;++k){
				int u=a[j+k],v=a[i+j+k]*w[i+k]%p;
				a[j+k]=sum(u,v);
				a[j+k+i]=minu(u,v);
			}
		}
	}
}
void idft(int *a,int N){
	reverse(a+1,a+N);
	dft(a,N);
	int iN=fpm(N,p-2)%p;
	for(int i=0;i<N;++i)a[i]=a[i]*iN%p;
}
int h1[1<<20|5],h2[1<<20|5],h3[1<<20|5],h4[1<<20|5],h5[1<<20|5];
void Inv(int *a,int n,int *b){
	b[0]=fpm(a[0],p-2);	
	/*for(int i=1;i<n;++i){
		b[i]=0;
		for(int j=1;j<=i;++j)b[i]=(b[i]+b[i-j]*a[j])%p;
		b[i]=(p-b[i])*b[0]%p;
	}
	assert(a[0]*b[0]%p==1);
	for(int i=1;i<n;++i){
		int s=0;
		for(int j=0;j<=i;++j)s=(s+a[j]*b[i-j])%p;
		assert(!s);
	}
	return;*/
	for(int i=1;i<n;++i)b[i]=0;
	int m=1;
	for(;m<n;m<<=1){
		int N=m<<2;
		upd(N);
		for(int i=0;i<m;++i){
			h1[i]=b[i];	
		}	
		for(int i=m;i<N;++i)h1[i]=0;
		for(int i=0;i<m<<1;++i)h2[i]=a[i];
		for(int i=m<<1;i<N;++i)h2[i]=0;
		dft(h1,N);
		dft(h2,N);
		for(int i=0;i<N;++i)h1[i]=h1[i]*h1[i]%p*h2[i]%p;
		idft(h1,N);
		for(int i=0;i<m<<1;++i)b[i]=(2*b[i]+p-h1[i])%p;
	}
	for(int i=n;i<m;++i)b[i]=0;
} 
void ln(int *a,int n,int *b){
	Inv(a,n,h3);
	int N=1;
	while(N<n+n)N<<=1;
	upd(N);
	for(int i=1;i<n;++i)h1[i-1]=a[i]*i%p;	
	for(int i=n-1;i<N;++i)h1[i]=0;
	for(int i=n;i<N;++i)h3[i]=0;
	dft(h1,N);
	dft(h3,N);
	for(int i=0;i<N;++i)h1[i]=h1[i]*h3[i]%p;
	idft(h1,N);
	b[0]=0;
	for(int i=1;i<n;++i)b[i]=h1[i-1]*inv[i]%p;
}
void exp(int *a,int n,int *b){
/*	b[0]=1;
	for(int i=1;i<n;++i){
		b[i]=0;
		for(int j=1;j<=i;++j)b[i]=(b[i]+b[i-j]*C(i-1,j-1)%p*a[j])%p;
	}
	return;*/
	b[0]=1;
	int m=1;
	for(;m<n;m<<=1){
		ln(b,m<<1,h4);
		for(int i=0;i<m<<1;++i)(h4[i]-=a[i])<0?h4[i]+=p:0;
		int N=m<<2;
		upd(N);
		for(int i=m<<1;i<N;++i)h4[i]=0;
		for(int i=0;i<m;++i)h1[i]=b[i];
		for(int i=m;i<N;++i)h1[i]=0;
		dft(h1,N);
		dft(h4,N);
		for(int i=0;i<N;++i)h1[i]=h1[i]*h4[i]%p;
		idft(h1,N);
		for(int i=0;i<m<<1;++i)b[i]=(b[i]+p-h1[i])%p;
	}
	for(int i=n;i<m;++i)b[i]=0;
}
signed main(){
#ifdef QAQAutoMaton 
	freopen("F.in","r",stdin);
	freopen("F.out","w",stdout);
#endif
	int n,m;	
	read(n,m);
	fac[0]=fac[1]=inv[1]=invf[0]=invf[1]=1;
	for(int i=2;i<=m;++i){
		fac[i]=fac[i-1]*i%p;
		inv[i]=(p-p/i)*inv[p%i]%p;
		invf[i]=inv[i]*invf[i-1]%p;
	}
	for(int i=0;i<=m;++i){
		f[i]=(m-i+1)*invf[i]%p;
	}
	nn=2;
	for(int i=1;i<nn;i<<=1){
		int xw=fpm(G,(p-1)/i/2),ww=1;
		for(int j=0;j<i;++j){
			w[i+j]=ww;
			ww=ww*xw%p;
		}
	}
	int s=f[0],is=fpm(s,p-2);
	for(int i=0;i<=m;++i)f[i]=f[i]*is%p;
	ln(f,m+1,g);
	for(int i=0;i<=m;++i){f[i]=g[i]*n%p;g[i]=0;}
	exp(f,m+1,g);
	s=fpm(s,n);
	for(int i=0;i<=m;++i)g[i]=g[i]*s%p;
	int ans=0;
	for(int i=0;i<=m;++i)ans=(ans+g[i]*invf[m-i]%p*fac[m])%p;
	write(ans,'\n');
	return 0;
}



Measured memory_bytes: 90368