long N=1024,d[1<<16],r;k,n,m,x,y,i;main(a){for(;~scanf("%d",&a);)n?k-=d[a]?0:++d[a]:(n=m,m=x,x=y,y=a);for(d[N]=k++;i<n*N-N;d[i+++N*2]=d[i]*k)for(m=N;m--;)d[i+N^m]+=d[m]*d[i];for(;x<N&x<=y;)r+=d[i+x++];printf("%d",r%998244353);}