#include using namespace std; #define rep(i, n) for (int i = 0; i < n; i++) #define rep2(i, x, n) for (int i = x; i <= n; i++) #define rep3(i, x, n) for (int i = x; i >= n; i--) #define each(e, v) for (auto &e : v) #define pb push_back #define eb emplace_back #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define sz(x) (int)x.size() using ll = long long; using pii = pair; using pil = pair; using pli = pair; using pll = pair; template bool chmax(T &x, const T &y) { return (x < y) ? (x = y, true) : false; } template bool chmin(T &x, const T &y) { return (x > y) ? (x = y, true) : false; } template int flg(T x, int i) { return (x >> i) & 1; } template void print(const vector &v, T x = 0) { int n = v.size(); for (int i = 0; i < n; i++) cout << v[i] + x << (i == n - 1 ? '\n' : ' '); if (v.empty()) cout << '\n'; } template void printn(const vector &v, T x = 0) { int n = v.size(); for (int i = 0; i < n; i++) cout << v[i] + x << '\n'; } template int lb(const vector &v, T x) { return lower_bound(begin(v), end(v), x) - begin(v); } template int ub(const vector &v, T x) { return upper_bound(begin(v), end(v), x) - begin(v); } template void rearrange(vector &v) { sort(begin(v), end(v)); v.erase(unique(begin(v), end(v)), end(v)); } template vector id_sort(const vector &v, bool greater = false) { int n = v.size(); vector ret(n); iota(begin(ret), end(ret), 0); sort(begin(ret), end(ret), [&](int i, int j) { return greater ? v[i] > v[j] : v[i] < v[j]; }); return ret; } template pair operator+(const pair &p, const pair &q) { return make_pair(p.first + q.first, p.second + q.second); } template pair operator-(const pair &p, const pair &q) { return make_pair(p.first - q.first, p.second - q.second); } template istream &operator>>(istream &is, pair &p) { S a; T b; is >> a >> b; p = make_pair(a, b); return is; } template ostream &operator<<(ostream &os, const pair &p) { return os << p.first << ' ' << p.second; } struct io_setup { io_setup() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout << fixed << setprecision(15); } } io_setup; const int inf = (1 << 30) - 1; const ll INF = (1LL << 60) - 1; // const int MOD = 1000000007; const int MOD = 998244353; template struct Mod_Int { int x; Mod_Int() : x(0) {} Mod_Int(long long y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {} static int get_mod() { return mod; } Mod_Int &operator+=(const Mod_Int &p) { if ((x += p.x) >= mod) x -= mod; return *this; } Mod_Int &operator-=(const Mod_Int &p) { if ((x += mod - p.x) >= mod) x -= mod; return *this; } Mod_Int &operator*=(const Mod_Int &p) { x = (int)(1LL * x * p.x % mod); return *this; } Mod_Int &operator/=(const Mod_Int &p) { *this *= p.inverse(); return *this; } Mod_Int &operator++() { return *this += Mod_Int(1); } Mod_Int operator++(int) { Mod_Int tmp = *this; ++*this; return tmp; } Mod_Int &operator--() { return *this -= Mod_Int(1); } Mod_Int operator--(int) { Mod_Int tmp = *this; --*this; return tmp; } Mod_Int operator-() const { return Mod_Int(-x); } Mod_Int operator+(const Mod_Int &p) const { return Mod_Int(*this) += p; } Mod_Int operator-(const Mod_Int &p) const { return Mod_Int(*this) -= p; } Mod_Int operator*(const Mod_Int &p) const { return Mod_Int(*this) *= p; } Mod_Int operator/(const Mod_Int &p) const { return Mod_Int(*this) /= p; } bool operator==(const Mod_Int &p) const { return x == p.x; } bool operator!=(const Mod_Int &p) const { return x != p.x; } Mod_Int inverse() const { assert(*this != Mod_Int(0)); return pow(mod - 2); } Mod_Int pow(long long k) const { Mod_Int now = *this, ret = 1; for (; k > 0; k >>= 1, now *= now) { if (k & 1) ret *= now; } return ret; } friend ostream &operator<<(ostream &os, const Mod_Int &p) { return os << p.x; } friend istream &operator>>(istream &is, Mod_Int &p) { long long a; is >> a; p = Mod_Int(a); return is; } }; using mint = Mod_Int; template struct Combination { static vector _fac, _ifac; Combination() {} static void init(int n) { _fac.resize(n + 1), _ifac.resize(n + 1); _fac[0] = 1; for (int i = 1; i <= n; i++) _fac[i] = _fac[i - 1] * i; _ifac[n] = _fac[n].inverse(); for (int i = n; i >= 1; i--) _ifac[i - 1] = _ifac[i] * i; } static T fac(int k) { return _fac[k]; } static T ifac(int k) { return _ifac[k]; } static T inv(int k) { return fac(k - 1) * ifac(k); } static T P(int n, int k) { if (k < 0 || n < k) return 0; return fac(n) * ifac(n - k); } static T C(int n, int k) { if (k < 0 || n < k) return 0; return fac(n) * ifac(n - k) * ifac(k); } static T H(int n, int k) { // k 個の区別できない玉を n 個の区別できる箱に入れる場合の数 if (n < 0 || k < 0) return 0; return k == 0 ? 1 : C(n + k - 1, k); } static T second_stirling_number(int n, int k) { // n 個の区別できる玉を、k 個の区別しない箱に、各箱に 1 個以上玉が入るように入れる場合の数 T ret = 0; for (int i = 0; i <= k; i++) { T tmp = C(k, i) * T(i).pow(n); ret += ((k - i) & 1) ? -tmp : tmp; } return ret * ifac(k); } static T bell_number(int n, int k) { // n 個の区別できる玉を、k 個の区別しない箱に入れる場合の数 if (n == 0) return 1; k = min(k, n); vector pref(k + 1); pref[0] = 1; for (int i = 1; i <= k; i++) { if (i & 1) { pref[i] = pref[i - 1] - ifac(i); } else { pref[i] = pref[i - 1] + ifac(i); } } T ret = 0; for (int i = 1; i <= k; i++) ret += T(i).pow(n) * ifac(i) * pref[k - i]; return ret; } }; template vector Combination::_fac = vector(); template vector Combination::_ifac = vector(); using comb = Combination; template struct Matrix { vector> A; Matrix(int m, int n) : A(m, vector(n, 0)) {} int height() const { return A.size(); } int width() const { return A.front().size(); } inline const vector &operator[](int k) const { return A[k]; } inline vector &operator[](int k) { return A[k]; } static Matrix I(int l) { Matrix ret(l, l); for (int i = 0; i < l; i++) ret[i][i] = 1; return ret; } Matrix &operator*=(const Matrix &B) { int m = height(), n = width(), p = B.width(); assert(n == B.height()); Matrix ret(m, p); for (int i = 0; i < m; i++) { for (int k = 0; k < n; k++) { for (int j = 0; j < p; j++) ret[i][j] += A[i][k] * B[k][j]; } } swap(A, ret.A); return *this; } Matrix operator*(const Matrix &B) const { return Matrix(*this) *= B; } Matrix pow(long long k) const { int m = height(), n = width(); assert(m == n); Matrix now = *this, ret = I(n); for (; k > 0; k >>= 1, now *= now) { if (k & 1) ret *= now; } return ret; } bool eq(const T &a, const T &b) const { return a == b; // return abs(a-b) <= EPS; } pair row_reduction(vector &b) { // 行基本変形を用いて簡約化を行い、(rank, det) の組を返す int m = height(), n = width(), check = 0, rank = 0; T det = 1; assert(b.size() == m); for (int j = 0; j < n; j++) { int pivot = check; for (int i = check; i < m; i++) { if (A[i][j] != 0) pivot = i; // if(abs(A[i][j]) > abs(A[pivot][j])) pivot = i; // T が小数の場合はこちら } if (check != pivot) det *= T(-1); swap(A[check], A[pivot]), swap(b[check], b[pivot]); if (eq(A[check][j], T(0))) { det = T(0); continue; } rank++; det *= A[check][j]; T r = T(1) / A[check][j]; for (int k = j + 1; k < n; k++) A[check][k] *= r; b[check] *= r; A[check][j] = T(1); for (int i = 0; i < m; i++) { if (i == check) continue; if (!eq(A[i][j], 0)) { for (int k = j + 1; k < n; k++) A[i][k] -= A[i][j] * A[check][k]; b[i] -= A[i][j] * b[check]; } A[i][j] = T(0); } if (++check == m) break; } return make_pair(rank, det); } pair row_reduction() { vector b(height(), T(0)); return row_reduction(b); } Matrix inverse() { // 行基本変形によって正方行列の逆行列を求める if (height() != width()) return Matrix(0, 0); int n = height(); Matrix ret = I(n); for (int j = 0; j < n; j++) { int pivot = j; for (int i = j; i < n; i++) { if (A[i][j] != 0) pivot = i; // if(abs(A[i][j]) > abs(A[pivot][j])) pivot = i; // T が小数の場合はこちら } swap(A[j], A[pivot]), swap(ret[j], ret[pivot]); if (eq(A[j][j], T(0))) return Matrix(0, 0); T r = T(1) / A[j][j]; for (int k = j + 1; k < n; k++) A[j][k] *= r; for (int k = 0; k < n; k++) ret[j][k] *= r; A[j][j] = T(1); for (int i = 0; i < n; i++) { if (i == j) continue; if (!eq(A[i][j], T(0))) { for (int k = j + 1; k < n; k++) A[i][k] -= A[i][j] * A[j][k]; for (int k = 0; k < n; k++) ret[i][k] -= A[i][j] * ret[j][k]; } A[i][j] = T(0); } } return ret; } vector> Gausiann_elimination(vector b) { // Ax = b の解の 1 つと解空間の基底の組を返す int m = height(), n = width(); row_reduction(b); vector> ret; vector p(m, n); vector is_zero(n, true); for (int i = 0; i < m; i++) { for (int j = 0; j < n; j++) { if (!eq(A[i][j], T(0))) { p[i] = j; break; } } if (p[i] < n) is_zero[p[i]] = false; else if (!eq(b[i], T(0))) return {}; } vector x(n, T(0)); for (int i = 0; i < m; i++) { if (p[i] < n) x[p[i]] = b[i]; } ret.push_back(x); for (int j = 0; j < n; j++) { if (!is_zero[j]) continue; x[j] = T(1); for (int i = 0; i < m; i++) { if (p[i] < n) x[p[i]] = -A[i][j]; } ret.push_back(x), x[j] = T(0); } return ret; } }; int main() { string S; int K; cin >> S >> K; int N = sz(S) / 2; using mat = Matrix; comb::init(N); mat A(N + 1, N + 1); rep(i, N + 1) { if (i > 0) A[i - 1][i] += i * i; if (i < N) A[i + 1][i] += (N - i) * (N - i); A[i][i] += 2 * i * (N - i) + N * (N - 1); } vector> dp(N + 1, vector(N + 1, 0)), ndp(N + 1, vector(N + 1, 0)); dp[0][0] = 1; rep(i, 2 * N) { rep(j, N + 1) rep(k, N + 1) ndp[j][k] = 0; rep(j, N + 1) { rep(k, N + 1) { if (dp[j][k] == 0) continue; { int nj = j, nk = k - 1; if (nj <= N && nk >= 0) ndp[nj][nk] += dp[j][k]; } { int nj = j + (S[i] == '('), nk = k + 1; if (nj <= N && nk <= N) ndp[nj][nk] += dp[j][k]; } } } swap(dp, ndp); } mat x(N + 1, 1); rep(i, N + 1) x[i][0] = dp[i][0]; x = A.pow(K) * x; cout << x[N][0] << '\n'; }