#include <bits/stdc++.h>
#define all(x) (x).begin(),(x).end()
using namespace std;

//#ifndef DLOCAL
//   #define cin fin
//   #define cout fout
//   ifstream cin(".in");
//   ofstream cout(".out");
//#endif

using ll = long long;
using ld = long double;

//#define int ll
#define sz(x) ((int)(x).size())

using pii = pair<int,int>;
using tii = tuple<int,int,int>;

const int mod = 998244353;
struct Mint {
   int val;
   Mint(ll x = 0): val((x % mod + mod) % mod) {;}
   Mint operator +(const Mint& x) const { return Mint(val + x.val); }
   Mint operator -(const Mint& x) const { return Mint(val - x.val); }
   Mint operator *(const Mint& x) const { return Mint((ll)val * x.val); }
   Mint operator +=(const Mint& x) { return *this = Mint(val + x.val); }
   Mint operator -=(const Mint& x) { return *this = Mint(val - x.val); }
   Mint operator *=(const Mint& x) { return *this = Mint((ll)val * x.val); }
   Mint operator ^(int b) const {
      Mint accum = 1, a = *this;
      while(b) {
         accum = (b & 1? accum * a : accum);
         a *= a;
         b >>= 1;
      }
      return accum;
   }
   Mint operator /(const Mint& x) { return Mint((ll)val * (x ^ (mod - 2)).val); }
   Mint operator /=(const Mint& x) { return *this = Mint((ll)val * (x ^ (mod - 2)).val); }
};
namespace COMBI {
   const int nmax = 1e5 + 5;  
   Mint fact[nmax], invfact[nmax];
   void init(int n = nmax - 1) {
      fact[0] = 1;
      for(int i = 1; i <= n; i++) fact[i] = fact[i - 1] * i;
      invfact[n] = Mint(1) / fact[n];
      for(int i = n; i > 0; i--) invfact[i - 1] = invfact[i] * Mint(i);
      return;
   }
   Mint f(int n) { return fact[n]; }
   Mint invf(int n) { return invfact[n]; }
   Mint ncr(int n, int r) { return fact[n] * invfact[r] * invfact[n - r]; }
}

const int nmax = 1e2 + 5;

Mint dp[nmax][nmax][nmax];
Mint spart[nmax][nmax][nmax];



signed main() {
   COMBI::init();
   cin.tie(0) -> sync_with_stdio(0);
   int n;
   cin >> n;
   
   vector<pii> val(n + 1);
   for(auto &[x, y] : val | views::drop(1)) cin >> x;
   for(auto &[x, y] : val | views::drop(1)) cin >> y;
   sort(1 + all(val));
   
   vector<int> second;
   {
      vector<int> freq(n + 1);
      for(auto &[a, b] : val) freq[b] = 1;
      for(int i = 1;  i <= n; i++) if(!freq[i]) second.emplace_back(i);
   }
   
   dp[0][0][0] = 1;
   for(int i = 0; i <= n; i++) spart[0][i][0] = 1;
   Mint total = COMBI::f(sz(second));
   
   for(int i = 1; i <= n; i++) {
      for(int chosen = 0; chosen <= min(sz(second), i); chosen++) {
         if(val[i].second != 0) {
            cerr << i << ' ' << val[i].second << ' ' << chosen << '\t' << spart[i - 1][val[i].second - 1][chosen].val << '\n';
            dp[i][val[i].second][chosen] += spart[i - 1][val[i].second - 1][chosen];
         }
         else if(chosen > 0) {
            for(auto x : second) dp[i][x][chosen] += spart[i - 1][x - 1][chosen - 1];
         }
      }
      for(int chosen = 0; chosen <= min(sz(second), i); chosen++) {
         for(int dim = 0; dim <= n; dim++) {
            total += dp[i][dim][chosen] * COMBI::f(sz(second) - chosen);
            spart[i][dim][chosen] = dp[i][dim][chosen];
            spart[i][dim][chosen] += spart[i - 1][dim][chosen];
            if(dim > 0) spart[i][dim][chosen] += spart[i][dim - 1][chosen] - spart[i - 1][dim - 1][chosen];
         }
      }
   }
   
   cout << total.val << '\n';
}

//10 + 9

//1 2 3 4
//2 3 4 1 




/**
      Ovaj podrum ima hladan sjaj\Iako je to bolje od gomile drugih
--
*/