#pragma GCC target("avx2") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using namespace atcoder; typedef long long ll; #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define repr(i, n) for (int i = (int)(n) - 1; i >= 0; i--) #define repk(i, k, n) for (int i = k; i < (int)(n); i++) #define all(v) v.begin(), v.end() #define mod1 1000000007 #define mod2 998244353 #define mod3 100000007 #define vi vector #define vs vector #define vc vector #define vl vector #define vb vector #define vvi vector> #define vvc vector> #define vvl vector> #define vvb vector> #define vvvi vector>> #define vvvl vector>> #define pii pair #define pil pair #define pli pair #define pll pair #define vpii vector> #define vpll vector> #define vvpii vector>> #define vvpll vector>> template void debug(T e) { cerr << e << endl; } template void debug(vector &v) { rep(i, v.size()) { cerr << v[i] << " "; } cerr << endl; } template void debug(vector> &v) { rep(i, v.size()) { rep(j, v[i].size()) { cerr << v[i][j] << " "; } cerr << endl; } } template void debug(vector> &v) { rep(i, v.size()) { cerr << v[i].first << " " << v[i].second << endl; } } template void debug(set &st) { for (auto itr = st.begin(); itr != st.end(); itr++) { cerr << *itr << " "; } cerr << endl; } template void debug(multiset &ms) { for (auto itr = ms.begin(); itr != ms.end(); itr++) { cerr << *itr << " "; } cerr << endl; } template void debug(map &mp) { for (auto itr = mp.begin(); itr != mp.end(); itr++) { cerr << itr->first << " " << itr->second << endl; } } void debug_out() { cerr << endl; } template void debug_out(Head H, Tail... T) { cerr << H << " "; debug_out(T...); } int main() { ll N; cin >> N; vector S(N); for (ll i = 0; i < N; i++) { cin >> S[i]; } string T = ""; for (ll i = 0; i < N; i++) { T += S[i]; } vector> pos(N * 16, vector(3, true)); for (ll i = 0; i < N * 16; i++) { if (T[i] == 'd') { pos[i][0] = false; pos[i][2] = false; } if (T[i] == 'k') { pos[i][0] = false; pos[i][1] = false; } if (T[i] == '.' && i < N * 16) { if (T[i + 1] == 'd') { pos[i][2] = false; } if (T[i + 1] == 'k') { pos[i][1] = false; } } } vector> dp(N * 16, vector(3)); for (ll i = 0; i < 3; i++) { if (pos[0][i]) { dp[0][i] = 1; } } for (ll i = 1; i < N * 16; i++) { if (i % 2 == 0) { for (ll j = 0; j < 3; j++) { if (pos[i][j]) { for (ll k = 0; k < 3; k++) { if (j == 0 && k != 0) { continue; } dp[i][j] += dp[i - 1][k]; dp[i][j] %= mod2; } } } } else { for (ll j = 0; j < 3; j++) { if (pos[i][j]) { for (ll k = 0; k < 3; k++) { if (k == 0 && j != 0) { continue; } dp[i][j] += dp[i - 1][k]; dp[i][j] %= mod2; } } } } } ll ans = 0; for (ll i = 0; i < 3; i++) { ans += dp[16 * N - 1][i]; ans %= mod2; } cout << ans << endl; }