#pragma GCC optimize("O3,unroll-loops") // #pragma GCC target("avx2,fma,popcnt,bmi,bmi2") #include #include using namespace std; using namespace atcoder; typedef int64_t lint; #define rep(i, n) for(int i=0; i; using vvi = vector>; template inline void vin(vector& v) { rep(i, v.size()) cin >> v.at(i); } template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } template inline void drop(T x) { cout << x << endl; exit(0); } template void vout(vector v) { rep(i, v.size()) { cout << v.at(i) << ' '; } cout << endl; } constexpr lint LINF = LLONG_MAX/2; using mint = modint998244353; using vm = vector; int main() { lint N; string S; cin >> N >> S; if (N%10) drop(0); lint a=0, b=0, c=0, x, y, z; vm dp(N/10+1); dp[0] = 1; rep(i, N/10) { if (!dp[i].val()) continue; repx(j, 1, N/10-i+1) { if (S[i*10+j*2] == 'o' && S[i*10+j*5] == 'o' && S[i*10+j*10] == 'o') { dp[i+j] += dp[i]; } } } std::cout << dp[N/10].val() << '\n'; }