#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define rd() ({long _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})
#define wt(v) {ulong _z=v;do*--wp=_z%10+48;while(_z/=10);}
#define rep(v,e) for(long v=0;v<e;++v)

typedef unsigned long ulong;

#define MD 998244353

int main(){
	long d;
	{
		char rbuf[64];
		read(0,rbuf,sizeof rbuf);
		char*rp=rbuf;
		long n=rd();
		long x=rd();
		long y=rd();
		if(x>y){
			long t=x;
			x=y;
			y=t;
		}
		d=y-x+(x<2)-(y<n);
	}
	long a=1,b=0,c=0;
	long d3=d/3;
	rep(i,d3){
		c+=b+=a+=c;
		c%=MD;
	}
	d%=3;
	c+=(d>0?a:0)+(d>1?b:0);
	c%=MD;
	{
		char wbuf[64],*wp=wbuf+sizeof wbuf;
		wt(c);
		write(1,wp,wbuf+sizeof wbuf-wp);
	}
	_exit(0);
}