#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 vi vector #define vs vector #define vc vector #define vl vector #define vvi vector> #define vvc vector> #define vvl 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; string S; cin >> S; vl sum(N + 1, 0); rep(i,N){ if (S[i] == '(') sum[i + 1] = sum[i] + 1; else sum[i + 1] = sum[i] - 1; } //debug(sum); //赤の状態から青の状態も一意に定まる. vvl dp(N + 1, vl(N + 1, 0));//dp[i][j] = (i番目まで見て,赤の余裕がj個あるような状態) dp[0][0] = 1; for (ll i = 0; i < N; i++){ for (ll j = 0; j <= N; j++){ if (S[i] == '('){ dp[i + 1][j + 1] = (dp[i + 1][j + 1] + dp[i][j]) % mod2; dp[i + 1][j] = (dp[i + 1][j] + dp[i][j]) % mod2; } else if (S[i] == ')'){ if (j > 0){ dp[i + 1][j - 1] = (dp[i + 1][j - 1] + dp[i][j]) % mod2; } if (j < sum[i]){ dp[i + 1][j] = (dp[i + 1][j] + dp[i][j]) % mod2; } } } } //debug(dp); cout << dp[N][0] << endl; }