#include<bits/stdc++.h>
#define LL long long
#define pb push_back
#define SZ(x) ((int)x.size()-1)
#define ms(a,b) memset(a,b,sizeof a)
#define F(i,a,b) for (int i=(a);i<=(b);++i)
#define DF(i,a,b) for (int i=(a);i>=(b);--i)
//#define mp make_pair
//#define OO(x) fixed<<setprecision(x)
using namespace std;
//mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
inline int read(){
	char ch=getchar(); int w=1,c=0;
	for(;!isdigit(ch);ch=getchar()) if (ch=='-') w=-1;
	for(;isdigit(ch);ch=getchar()) c=(c<<1)+(c<<3)+(ch^48);
	return w*c;
}
const int M=105,mod=998244353; 
int n,p[M],pre[M],a[M],in[M];
void red(int &x){
	x=(x>=mod ? x-mod : x);
}
int dp[M][M][M];
LL C[M][M],fac[M];
void init(){
	F(i,0,n){
		C[i][0]=1; 
		F(j,1,i){
			C[i][j]=(C[i-1][j]+C[i-1][j-1])%mod;
		}
	}
	fac[0]=1;
	F(i,1,n) fac[i]=fac[i-1]*i%mod;
}
int main(){
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	n=read(); init();
	F(i,1,n) p[i]=read();
	F(i,1,n){
		int x=read();
		a[p[i]]=x; in[x]=1;
	}
	F(i,1,n) pre[i]=pre[i-1]+(!in[i]);
	dp[0][0][0]=1;
	int z=0;
	F(i,1,n){
		F(j,0,n){
			F(k,0,j){
				if (dp[i-1][j][k]){
//					cerr<<i-1<<" "<<j<<" "<<k<<" "<<dp[i-1][j][k]<<"  dp \n";
					LL tmp=dp[i-1][j][k];
					if (a[i]){
						if (a[i]<j){
							red(dp[i][j][k]+=tmp);
						}
						else{
							red(dp[i][j][k]+=tmp);
							
							//max change 
							int num=pre[a[i]]-pre[j],no=z-(pre[j]-k);
							F(l,0,min(no,num)){
								LL coe=C[no][l]*C[num][l]%mod*fac[l]%mod;
								dp[i][a[i]][k+num-l]=(dp[i][a[i]][k+num-l]+coe*tmp)%mod;
							}
						}
					}
					else{
						if (k) dp[i][j][k-1]=(dp[i][j][k-1]+tmp*k)%mod;//one
						red(dp[i][j][k]+=tmp);//zero
						F(l,j+1,n){
							if (in[l]) continue;
							int num=pre[l]-pre[j]-1,no=z-(pre[j]-k);
							F(o,0,min(no,num)){
								LL coe=C[no][o]*C[num][o]%mod*fac[o]%mod;
								dp[i][l][k+num-o]=(dp[i][l][k+num-o]+coe*tmp)%mod;
							}
						}
					}
				}
			}
		}	
		z+=(!a[i]);
	}
	LL ans=0;
	F(i,0,n) ans=(ans+dp[n][i][0]*fac[pre[n]-pre[i]])%mod;
	cout<<ans<<'\n';
	//dp[n][i][0]
	return 0;
}
/* stuff you should look for
	* int overflow, array bounds
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
	* DON'T GET STUCK ON ONE APPROACH
*/