#include <bits/stdc++.h>
#define _rep(i, x, y) for(int i = x; i <= y; ++i)
#define _req(i, x, y) for(int i = x; i >= y; --i)
#define _rev(i, u) for(int i = head[u]; i; i = e[i].nxt)
#define pb push_back
#define fi first
#define se second
#define mst(f, i) memset(f, i, sizeof f)
using namespace std;
#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#endif
typedef long long ll;
typedef pair<int, int> PII;
namespace fastio{
    #ifdef ONLINE_JUDGE
    char ibuf[1 << 20],*p1 = ibuf, *p2 = ibuf;
    #define get() p1 == p2 && (p2 = (p1 = ibuf) + fread(ibuf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++
    #else
    #define get() getchar()
    #endif
    template<typename T> inline void read(T &t){
        T x = 0, f = 1;
        char c = getchar();
        while(!isdigit(c)){
            if(c == '-') f = -f;
            c = getchar();
        }
        while(isdigit(c)) x = x * 10 + c - '0', c = getchar();
        t = x * f;
    }
    template<typename T, typename ... Args> inline void read(T &t, Args&... args){
        read(t);
        read(args...);
    }
    template<typename T> void write(T t){
        if(t < 0) putchar('-'), t = -t;
        if(t >= 10) write(t / 10);
        putchar(t % 10 + '0');
    }
    template<typename T, typename ... Args> void write(T t, Args... args){
        write(t), putchar(' '), write(args...);
    }
    template<typename T> void writeln(T t){
        write(t);
        puts("");
    }
    template<typename T> void writes(T t){
        write(t), putchar(' ');
    }
    #undef get
};
using namespace fastio;
#define multitest() int T; read(T); _rep(tCase, 1, T)
namespace Calculation{
    const ll mod = 998244353;
    ll ksm(ll p, ll h){ll base = p % mod, res = 1; while(h){if(h & 1ll) res = res * base % mod; base = base * base % mod, h >>= 1ll;} return res;}
    void dec(ll &x, ll y){x = ((x - y) % mod + mod) % mod;}
    void add(ll &x, ll y){x = (x + y) % mod;}
    void mul(ll &x, ll y){x = x * y % mod;}
    ll sub(ll x, ll y){return ((x - y) % mod + mod) % mod;}
    ll pls(ll x, ll y){return ((x + y) % mod + mod) % mod;}
    ll mult(ll x, ll y){return x * y % mod;}
}
using namespace Calculation;
const int N = 2e5 + 5;
ll n, a[N], fac[N], ifac[N], b[N];
char s[N];
ll f[N][2];
ll C(ll n, ll m){
    if(n < m || m < 0) return 0;
    if(n == m || !m) return 1;
    return fac[n] * ifac[m] % mod * ifac[n - m] % mod;
}
int main(){
    read(n);
    fac[0] = ifac[0] = fac[1] = ifac[1] = 1;
    _rep(i, 2, n) fac[i] = fac[i - 1] * i % mod, ifac[i] = (mod - mod / i) * ifac[mod % i] % mod;
    _rep(i, 2, n) ifac[i] = ifac[i - 1] * ifac[i] % mod;
    _rep(i, 1, n) read(a[i]); scanf("%s", s + 1);
    _rep(i, 1, n - 1) b[i] = s[i] == '+' ? 0 : 1;
    ll ans = 0;
    _rep(i, 1, n){
        f[i][0] = 1, f[i][1] = 0;
        _req(j, i - 1, 1){
            _rep(k, 0, 1) f[j][k] = (f[j + 1][k ^ b[j]] + f[j + 1][k] * (i - j - 1) % mod) % mod;
        }
        ll cur = C(n - 1, i - 1) * fac[n - i] % mod;
        add(ans, f[1][0] * cur % mod * a[i] % mod + f[1][1] * cur % mod * (mod - a[i]) % mod);
    }
    writeln(ans);
    return 0;
}