#define MD 998244353
Comb<Mint>c;
ll@n,@m,@a[n],@b[n];
Mint e[m][1024];
rep(k,m){
	rep(j,601){
		e[k][j]=1;
	}
}
rep(i,n){
	rep(j,601){
		e[i%m][j]*=c.C(a[i]+b[i],j-300+b[i]);
	}
}
Mint g[1<<17];
g[0]=1;
fft(1<<17,g);
rep(k,m){
	Mint h[1<<17];
	rep(i,1024){
		h[i]=e[k][i];
	}
	fft(1<<17,h);
	rep(i,1<<17){
		g[i]*=h[i];
	}
}
fftinv(1<<17,g);
wt(g[m*300]/(1<<17));