#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const ll mod = 998244353;
const int maxn = 2e5 + 5;

ll fpow(ll a, ll b)
{
    ll ans = 1;
    while (b)
    {
        if (b & 1) ans = ans * a % mod;
        a = a * a % mod;
        b >>= 1;
    }
    return ans;
}

int len, lim, rev[maxn];

void NTT(vector<ll> &p, int fl)
{
    for (int i = 0; i < lim; i++)
        if (i < rev[i]) swap(p[i], p[rev[i]]);
    
    ll x = fl == 1 ? 3 : 332748118;
    for (int i = 1; i < lim; i <<= 1)
    {
        ll T = fpow(x, (mod - 1) / i / 2);
        for (int j = 0; j < lim; j += (i << 1))
        {
            ll t = 1;
            for (int k = 0; k < i; k++, t = t * T % mod)
            {
                ll X = p[j + k], Y = t * p[i + j  + k] % mod;
                p[j + k] = (X + Y) % mod, p[i + j + k] = (X + mod - Y) % mod;
            }
        }
    }
    if (fl == -1)
    {
        ll inv = fpow(lim, mod - 2);
        for (int i = 0; i < lim; i++) (p[i] *= inv) %= mod;
    }
}

inline void preNTT(int x)
{
    len = 0, lim = 1;
    while (lim <= x) lim <<= 1, len++;
    for (int i = 0; i < lim; i++) rev[i] = (rev[i >> 1] >> 1) | ((i & 1) << (len - 1));
}

int n;
char s[maxn];
bool dt[maxn][2], cr[maxn][2];

struct info
{
    vector<ll> f[2][2];
    info() { f[0][0].clear(); f[0][1].clear(); f[1][0].clear(); f[1][1].clear(); }
    info operator * (info b)
    {
        int mx = 0;
        for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++) for (int k = 0; k < 2; k++)
            mx = max(mx, (int)f[i][j].size() + (int)b.f[j][k].size());
        preNTT(mx);
        for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++)
        {
            while (f[i][j].size() < lim) f[i][j].emplace_back(0);
            while (b.f[i][j].size() < lim) b.f[i][j].emplace_back(0);
            NTT(f[i][j], 1), NTT(b.f[i][j], 1);
        }
        info ans; for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++) ans.f[i][j].resize(lim);
        for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++) for (int k = 0; k < 2; k++)
            for (int t = 0; t < lim; t++) (ans.f[i][j][t] += f[i][k][t] * b.f[k][j][t]) %= mod;
        for (int i = 0; i < 2; i++) for (int j = 0; j < 2; j++)
        {
            NTT(ans.f[i][j], -1);
            while (!ans.f[i][j].back())ans.f[i][j].pop_back();
        }
        return ans;
    }
};

info DivideFFT(int l, int r)
{
    if (l == r)
    {
        info res;
        if (cr[l][0] && cr[l + 1][0]) res.f[0][0] = {0, dt[l][0] + dt[l][1]};
        if (cr[l][1] && cr[l + 1][1]) res.f[1][1] = {0, dt[l][0] + dt[l][1]};
        if (cr[l][0] && cr[l + 1][1]) res.f[0][1] = {dt[l][0], dt[l][1]};
        if (cr[l][1] && cr[l + 1][0]) res.f[1][0] = {0, dt[l][1], dt[l][0]};
        return res;
    }
    int mid = (l + r) >> 1;
    return DivideFFT(l, mid) * DivideFFT(mid + 1, r);
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    cin >> n >> s + 1;
    for (int i = 1; i <= n; i++) cr[i][1] = (s[2 * i - 1] != 'P'), cr[i][0] = (s[2 * i - 1] != 'Y');
    for (int i = 1; i <= n; i++) dt[i][1] = (s[2 * i] != 'R'), dt[i][0] = (s[2 * i] != 'B');
    cr[n + 1][0] = cr[1][0], cr[n + 1][1] = cr[1][1];

    info ans = DivideFFT(1, n);
    cout << (ans.f[0][0][n] + ans.f[1][1][n]) % mod;
    return 0;
}