#include<bits/stdc++.h>
using namespace std;
#ifdef DEBUG
#include"debug.h"
#else
#define debug(...) void()
#endif
#define all(x) (x).begin(),(x).end()
template<class T>
auto ary(T *a,int l,int r){
	return vector<T>{a+l,a+1+r};
}
using ll=long long;
using ull=unsigned long long;
const int M=3,mod=998244353;
ll qpow(ll x,ll y=mod-2,ll ans=1){
	for(;y;(x*=x)%=mod,y>>=1)if(y&1)(ans*=x)%=mod;
	return ans;
}
using vec=array<int,M>;
using matrix=array<vec,M>;
#ifdef DEBUG
ostream& operator << (ostream &out,vec a){
	out<<'[';
	for(int i=0;i<M;i++)out<<a[i]<<',';
	return out<<']';
}
ostream& operator << (ostream &out,matrix a){
	out<<'[';
	for(int i=0;i<M;i++)out<<a[i]<<',';
	return out<<']';
}
#endif
vec operator * (const vec &a,const matrix &b){
	static vec c;
	c.fill(0);
	for(int i=0;i<M;i++){
		for(int j=0;j<M;j++){
			c[j]=(c[j]+1ll*a[i]*b[i][j])%mod;
		}
	}
	return c;
}
matrix operator * (const matrix &a,const matrix &b){
	static matrix c;
	for(int i=0;i<M;i++)c[i]=a[i]*b;
	return c;
}
vec operator + (const vec &a,const vec &b){
	static vec c;
	for(int i=0;i<M;i++)c[i]=(a[i]+b[i])%mod;
	return c;
}
vec operator * (const vec &a,const int &k){
	static vec b;
	for(int i=0;i<M;i++)b[i]=1ll*a[i]*k%mod;
	return b;
}
int n,m;
matrix base;
vec ans;
int f[32][2];
void add(int &x,ll y){
	x=(x+y)%mod;
}
int main(){
	cin>>n>>m;
	ans[0]=3,ans[2]=2;
	base[1][0]=1,base[2][1]=1;
	base[0][2]=1,base[1][2]=1;
	for(int y=n;y;y>>=1,base=base*base)if(y&1)ans=ans*base;
	f[0][0]=1;
	for(int i=0;i<=30;i++){
		if(m>>i&1){
			f[i+1][0]=(f[i][1]+1ll*f[i][0]*ans[0])%mod;
			f[i+1][1]=f[i][1];
		}else{
			f[i+1][0]=f[i][0];
			f[i+1][1]=(1ll*f[i][1]*ans[0]+f[i][0])%mod;
		}
	}
	cout<<f[31][0]<<endl;
	return 0;
}
#ifdef DEBUG
#include"debug.hpp"
#endif