/* #region Head */ // #define _GLIBCXX_DEBUG #include using namespace std; using ll = long long; using ull = unsigned long long; using ld = long double; using pll = pair; template using vc = vector; template using vvc = vc>; using vll = vc; using vvll = vvc; using vld = vc; using vvld = vvc; using vs = vc; using vvs = vvc; template using um = unordered_map; template using pq = priority_queue; template using pqa = priority_queue, greater>; template using us = unordered_set; #define REP(i, m, n) for (ll i = (m), i##_len = (ll)(n); i < i##_len; ++(i)) #define REPM(i, m, n) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; ++(i)) #define REPR(i, m, n) for (ll i = (m), i##_min = (ll)(n); i >= i##_min; --(i)) #define REPD(i, m, n, d) for (ll i = (m), i##_len = (ll)(n); i < i##_len; i += (d)) #define REPMD(i, m, n, d) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; i += (d)) #define REPI(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++) #define ALL(x) begin(x), end(x) #define SIZE(x) ((ll)(x).size()) #define PERM(c) \ sort(ALL(c)); \ for (bool c##p = 1; c##p; c##p = next_permutation(ALL(c))) #define UNIQ(v) v.erase(unique(ALL(v)), v.end()); #define endl '\n' #define sqrt sqrtl #define floor floorl #define log2 log2l constexpr ll INF = 1'010'000'000'000'000'017LL; constexpr ll MOD = 1'000'000'007LL; // 1e9 + 7 constexpr ld EPS = 1e-12; constexpr ld PI = 3.14159265358979323846; template istream &operator>>(istream &is, vc &vec) { // vector 入力 for (T &x : vec) is >> x; return is; } template ostream &operator<<(ostream &os, vc &vec) { // vector 出力 (for dump) os << "{"; REP(i, 0, SIZE(vec)) os << vec[i] << (i == i_len - 1 ? "" : ", "); os << "}"; return os; } template ostream &operator>>(ostream &os, vc &vec) { // vector 出力 (inline) REP(i, 0, SIZE(vec)) os << vec[i] << (i == i_len - 1 ? "\n" : " "); return os; } template istream &operator>>(istream &is, pair &pair_var) { // pair 入力 is >> pair_var.first >> pair_var.second; return is; } template ostream &operator<<(ostream &os, pair &pair_var) { // pair 出力 os << "(" << pair_var.first << ", " << pair_var.second << ")"; return os; } // map, um, set, us 出力 template ostream &out_iter(ostream &os, T &map_var) { os << "{"; REPI(itr, map_var) { os << *itr; auto itrcp = itr; if (++itrcp != map_var.end()) os << ", "; } return os << "}"; } template ostream &operator<<(ostream &os, map &map_var) { return out_iter(os, map_var); } template ostream &operator<<(ostream &os, um &map_var) { os << "{"; REPI(itr, map_var) { auto [key, value] = *itr; os << "(" << key << ", " << value << ")"; auto itrcp = itr; if (++itrcp != map_var.end()) os << ", "; } os << "}"; return os; } template ostream &operator<<(ostream &os, set &set_var) { return out_iter(os, set_var); } template ostream &operator<<(ostream &os, us &set_var) { return out_iter(os, set_var); } template ostream &operator<<(ostream &os, pq &pq_var) { pq pq_cp(pq_var); os << "{"; if (!pq_cp.empty()) { os << pq_cp.top(), pq_cp.pop(); while (!pq_cp.empty()) os << ", " << pq_cp.top(), pq_cp.pop(); } return os << "}"; } // dump #define DUMPOUT cerr void dump_func() { DUMPOUT << endl; } template void dump_func(Head &&head, Tail &&... tail) { DUMPOUT << head; if (sizeof...(Tail) > 0) DUMPOUT << ", "; dump_func(move(tail)...); } // chmax (更新「される」かもしれない値が前) template > bool chmax(T &xmax, const U &x, Comp comp = {}) { if (comp(xmax, x)) { xmax = x; return true; } return false; } // chmin (更新「される」かもしれない値が前) template > bool chmin(T &xmin, const U &x, Comp comp = {}) { if (comp(x, xmin)) { xmin = x; return true; } return false; } // ローカル用 #define DEBUG_ #ifdef DEBUG_ #define DEB #define dump(...) \ DUMPOUT << " " << string(#__VA_ARGS__) << ": " \ << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" << endl \ << " ", \ dump_func(__VA_ARGS__) #else #define DEB if (false) #define dump(...) #endif struct AtCoderInitialize { static constexpr int IOS_PREC = 15; static constexpr bool AUTOFLUSH = false; AtCoderInitialize() { ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr); cout << fixed << setprecision(IOS_PREC); if (AUTOFLUSH) cout << unitbuf; } } ATCODER_INITIALIZE; void Yn(bool p) { cout << (p ? "Yes" : "No") << endl; } void YN(bool p) { cout << (p ? "YES" : "NO") << endl; } /* #endregion */ /* #region mint */ // 自動で MOD を取る整数 struct mint { ll x; mint(ll x = 0) : x((x % MOD + MOD) % MOD) {} mint &operator+=(const mint a) { if ((x += a.x) >= MOD) x -= MOD; return *this; } mint &operator-=(const mint a) { if ((x += MOD - a.x) >= MOD) x -= MOD; return *this; } mint &operator*=(const mint a) { (x *= a.x) %= MOD; return *this; } mint operator+(const mint a) const { mint res(*this); return res += a; } mint operator-(const mint a) const { mint res(*this); return res -= a; } mint operator*(const mint a) const { mint res(*this); return res *= a; } // O(log(t)) mint pow(ll t) const { if (!t) return 1; mint a = pow(t >> 1); // ⌊t/2⌋ 乗 a *= a; // ⌊t/2⌋*2 乗 if (t & 1) // ⌊t/2⌋*2 == t-1 のとき a *= *this; // ⌊t/2⌋*2+1 乗 => t 乗 return a; } // for prime mod mint inv() const { return pow(MOD - 2); // オイラーの定理から, x^(-1) ≡ x^(p-2) } mint &operator/=(const mint a) { return (*this) *= a.inv(); } mint operator/(const mint a) const { mint res(*this); return res /= a; } bool operator==(const mint a) const { return this->x == a.x; } bool operator==(const ll a) const { return this->x == a; } // mint 入力 friend istream &operator>>(istream &is, mint &x) { is >> x.x; return is; } // mint 出力 friend ostream &operator<<(ostream &os, mint x) { os << x.x; return os; } }; /* #endregion */ /* #region zAlgo */ // T: operator[]() と size() が使えるシーケンス template vc zAlgorithm(T &S) { int sz = SIZE(S), i = 1, j = 0; vc Z(sz); Z[0] = sz; while (i < sz) { while (i + j < sz && S[j] == S[i + j]) ++j; Z[i] = j; if (j == 0) { ++i; continue; } int k = 1; while (i + k < sz && k + Z[k] < j) Z[i + k] = Z[k], ++k; i += k, j -= k; } return Z; } /* #endregion */ // Problem void solve() { string s; cin >> s; ll sz = SIZE(s); // dp[i] := 先頭・末尾の要素それぞれ i 個が分解可能で, // それ以外の中間部分を分解しないままにした場合の分解の場合の数 vc dp(sz / 2 + 1, 0); dp[0] = 1; // 全体を分解しないままにした場合の分解の場合の数 REP(i, 0, (sz + 1) / 2) { // 先頭・末尾から i 文字削った文字列の Z 配列をつくる ll len = sz - 2 * i; string ss = s.substr(i, len); vc Z = zAlgorithm(ss); // 末尾の区間が先頭からの区間と一致している場合,パターン数を配る REPM(j, 1, len / 2) { // dump(i, j, i + j, sz / 2 + 1); if (Z[len - j] == j) dp[i + j] += dp[i]; // 配る } } cout << accumulate(ALL(dp), mint(0)) << endl; } // entry point int main() { solve(); return 0; }