#include<algorithm>
#include<bitset>
#include<iostream>
#include<iomanip>
#include<set>
#include<string>
#include<math.h>
#include<stack>
#include<string>
#include<queue>
#include<vector>
using namespace std;
typedef long long int ll;
typedef pair<int, ll> P;

//--------------
///#define DEBUG
//--------------

#ifdef DEBUG
	#define debugprint(x) cout<<x<<" "
	#define debugendl cout<<endl
	#define debug(x) x
#else
	#define debugprint(x)
	#define debugendl
	#define debug(x)
#endif

class zahyo{
	public:
	int x;
	int y;
	zahyo(){
		x=0;
		y=0;
	}
	zahyo(int x_,int y_){
		x=x_;
		y=y_;
	}
	void print(){
		cout<<x<<" "<<y;
	}
	zahyo operator+(zahyo add){
		add.x=this->x+add.x;
		add.y=this->y+add.y;
		return add;
	}
	zahyo operator-(zahyo add){
		add.x=this->x-add.x;
		add.y=this->y-add.y;
		return add;
	}
	zahyo operator*(int t){
		zahyo temp;
		temp.x=this->x*t;
		temp.y=this->y*t;
		return temp;
	}
	zahyo operator%(int t){
		zahyo temp(this->x%t,this->y%t);
		return temp;
	}
	zahyo operator/(int t){
		zahyo temp(this->x/t,this->y/t);
		return temp;
	}
	bool operator==(const zahyo add) const{
		if(add.x==this->x and add.y==this->y){return true;}
		else{return false;}
	}
	bool operator!=(const zahyo add) const{
		if(add.x==this->x or add.y==this->y){return false;}
		else{return true;}
	}
	bool operator<(const zahyo add) const{
		if(this->x<add.x){return true;}
		else if(this->x==add.x and this->y<add.y){return true;}
		else{return false;}
	}
	bool operator>(const zahyo add) const{
		if(this->x>add.x){return true;}
		else if(this->x==add.x and this->y>add.y){return true;}
		else{return false;}
	}
	void input(){
		cin>>x>>y;
	}
};



long long int beki(long long int a,long long int n){
  long long int x = 1LL;
  n%=998244352LL;
  while(n > 0){
    if(n&1LL){
      x = x*a;
    }
    x%=998244353LL;
    a = a*a;
    a%=998244353LL;
    n >>= 1;
  }
  return x;
}

int main(){
	long long int a,b;
	cin>>a>>b;
	long long int c=a/b;
	if(a%b!=0){c++;}
	long long int ans=beki(2LL,c);
	ans%=998244353LL;
	cout<<ans-1<<endl;
	return 0;
}