func_code_string: #include <bits/stdc++.h>   #pragma warning(disable : 4996)   using namespace std;   using ld = long double;   template <class T>   using Table = vector<vector<T>>;   const ld eps = 1e-9;   template <class S, class T>   ostream &operator<<(ostream &os, const pair<S, T> v) {     os <<  (   << v.first <<  ,   << v.second <<  ) ;     return os;   }   template <class T>   ostream &operator<<(ostream &os, const vector<T> &v) {     for (int i = 0; i < v.size(); i++) {       if (i > 0) {         os <<    ;       }       os << v[i];     }     return os;   }   template <class T>   ostream &operator<<(ostream &os, const vector<vector<T>> &v) {     for (int i = 0; i < v.size(); i++) {       if (i > 0) {         os << endl;       }       os << v[i];     }     return os;   }   template <class T>   ostream &operator<<(ostream &os, const vector<set<T>> &v) {     for (int i = 0; i < v.size(); i++) {       if (i > 0) {         os << endl;       }       os << v[i];     }     return os;   }   template <class T>   ostream &operator<<(ostream &os, const map<T, T> &v) {     int i = 0;     for (auto it : v) {       if (i > 0) {         os <<    ;       }       os << it.first <<     << it.second;       i++;     }     return os;   }   using ll = long long;   const int mod = 998244353;   struct Mod {    public:     int num;     Mod() : Mod(0) { ; }     Mod(long long int n) : num((n % mod + mod) % mod) {       static_assert(mod < INT_MAX / 2,                      mod is too big, please make num  long long int  from  int  );     }     Mod(int n) : Mod(static_cast<long long int>(n)) { ; }     operator int() { return num; }   };   Mod operator+(const Mod a, const Mod b) { return Mod((a.num + b.num) % mod); }   Mod operator+(const long long int a, const Mod b) { return Mod(a) + b; }   Mod operator+(const Mod a, const long long int b) { return b + a; }   Mod operator++(Mod &a) { return a + Mod(1); }   Mod operator-(const Mod a, const Mod b) {     return Mod((mod + a.num - b.num) % mod);   }   Mod operator-(const long long int a, const Mod b) { return Mod(a) - b; }   Mod operator--(Mod &a) { return a - Mod(1); }   Mod operator*(const Mod a, const Mod b) {     return Mod(((long long)a.num * b.num) % mod);   }   Mod operator*(const long long int a, const Mod b) { return Mod(a) * b; }   Mod operator*(const Mod a, const long long int b) { return Mod(b) * a; }   Mod operator*(const Mod a, const int b) { return Mod(b) * a; }   Mod operator+=(Mod &a, const Mod b) { return a = a + b; }   Mod operator+=(long long int &a, const Mod b) { return a = a + b; }   Mod operator-=(Mod &a, const Mod b) { return a = a - b; }   Mod operator-=(long long int &a, const Mod b) { return a = a - b; }   Mod operator*=(Mod &a, const Mod b) { return a = a * b; }   Mod operator*=(long long int &a, const Mod b) { return a = a * b; }   Mod operator*=(Mod &a, const long long int &b) { return a = a * b; }   Mod operator^(const Mod a, const int n) {     if (n == 0) return Mod(1);     Mod res = (a * a) ^ (n / 2);     if (n % 2) res = res * a;     return res;   }   Mod mod_pow(const Mod a, const long long n) {     if (n == 0) return Mod(1);     Mod res = mod_pow((a * a), (n / 2));     if (n % 2) res = res * a;     return res;   }   Mod inv(const Mod a) { return a ^ (mod - 2); }   Mod operator/(const Mod a, const Mod b) {     assert(b.num != 0);     return a * inv(b);   }   Mod operator/(const long long int a, const Mod b) { return Mod(a) / b; }   Mod operator/=(Mod &a, const Mod b) { return a = a / b; }   Mod fact[1024000], factinv[1024000];   void init(const int amax = 1024000) {     fact[0] = Mod(1);     factinv[0] = 1;     for (int i = 0; i < amax - 1; ++i) {       fact[i + 1] = fact[i] * Mod(i + 1);       factinv[i + 1] = factinv[i] / Mod(i + 1);     }   }   Mod comb(const int a, const int b) {     return fact[a] * factinv[b] * factinv[a - b];   }   using Value = pair<Mod, Mod>;   const Value ini = make_pair(Mod(1), Mod(0));   Value connect(Value al, const Value ar) {     return make_pair(al.first * ar.first, al.second * ar.first + ar.second);   }   Value dat[800001];   struct segtree {     int N;     segtree() {}     segtree(int n) {       N = 1;       while (N < n) N *= 2;       for (int x = 0; x < N; ++x) {         { dat[x + N - 1] = ini; }       }       for (int x = N - 2; x >= 0; --x) {         dat[x] = connect(dat[x * 2 + 1], dat[x * 2 + 2]);       }     }     void update(int k, const Value &a) {       k += N - 1;       dat[k] = a;       while (k > 0) {         k = (k - 1) >> 1;         dat[k] = connect(dat[k * 2 + 1], dat[k * 2 + 2]);       }     }     Value query(int a, int b) { return query(a, b, 0, 0, N); }     Value query(int a, int b, int k, int l, int r) {       if (r <= a or b <= l) return ini;       if (a <= l and r <= b) return dat[k];       const int m = (l + r) / 2;       return connect(query(a, b, k * 2 + 1, l, m), query(a, b, k * 2 + 2, m, r));     }   };   pair<Mod, Mod> dp[2010][2010];   int flag[2010][2010];   string st;   pair<Mod, Mod> solve(int l, int r) {     if (flag[l][r]) {       return dp[l][r];     }     flag[l][r] = true;     if (l == r) {       return dp[l][r] = make_pair(Mod(st[l] ==  ?  ? 2 : 1), Mod(0));     } else if (l - 1 == r) {       return dp[l][r] = make_pair(Mod(1), Mod(0));     }     if (st[l] ==  ( ) {       if (st[r] ==  ( ) {         dp[l][r] = solve(l, r - 1);       } else if (st[r] ==  ? ) {         auto ap = solve(l + 1, r - 1);         auto bp = solve(l, r - 1);         dp[l][r] =             make_pair(ap.first + bp.first, ap.second + bp.second + ap.first);       } else {         auto ap = solve(l + 1, r - 1);         dp[l][r] = make_pair(ap.first, ap.second + ap.first);       }     } else if (st[l] ==  ) ) {       dp[l][r] = solve(l + 1, r);     } else {       if (st[r] ==  ( ) {         dp[l][r] = solve(l, r - 1);       } else if (st[r] ==  ? ) {         auto ap = solve(l + 1, r - 1);         auto bp = solve(l, r - 1);         auto cp = solve(l + 1, r);         auto ep = solve(l + 1, r - 1);         ap.second += ap.first;         dp[l][r].first += ap.first + bp.first + cp.first - ep.first;         dp[l][r].second += ap.second + bp.second + cp.second - ep.second;       } else {         auto ap = solve(l + 1, r - 1);         ap.second += ap.first;         auto bp = solve(l + 1, r);         dp[l][r] = make_pair(ap.first + bp.first, ap.second + bp.second);       }     }     return dp[l][r];   }   int main() {     ios::sync_with_stdio(false);     cin >> st;     auto answer = solve(0, int(st.size()) - 1);     cout << answer.second << endl;     return 0;   }   