# include "bits/stdc++.h" using namespace std; using LL = long long; using ULL = unsigned long long; const double PI = acos(-1); templateconstexpr T INF() { return ::std::numeric_limits::max(); } templateconstexpr T HINF() { return INF() / 2; } template T_char TL(T_char cX) { return tolower(cX); }; template T_char TU(T_char cX) { return toupper(cX); }; typedef pair pii; const int vy[] = { -1, -1, -1, 0, 1, 1, 1, 0 }, vx[] = { -1, 0, 1, 1, 1, 0, -1, -1 }; const int dx[4] = { 0,1,0,-1 }, dy[4] = { 1,0,-1,0 }; int popcnt(unsigned long long n) { int cnt = 0; for (int i = 0; i < 64; i++)if ((n >> i) & 1)cnt++; return cnt; } int d_sum(LL n) { int ret = 0; while (n > 0) { ret += n % 10; n /= 10; }return ret; } int d_cnt(LL n) { int ret = 0; while (n > 0) { ret++; n /= 10; }return ret; } LL gcd(LL a, LL b) { if (b == 0)return a; return gcd(b, a%b); }; LL lcm(LL a, LL b) { LL g = gcd(a, b); return a / g*b; }; # define ALL(qpqpq) (qpqpq).begin(),(qpqpq).end() # define UNIQUE(wpwpw) sort(ALL((wpwpw)));(wpwpw).erase(unique(ALL((wpwpw))),(wpwpw).end()) # define LOWER(epepe) transform(ALL((epepe)),(epepe).begin(),TL) # define UPPER(rprpr) transform(ALL((rprpr)),(rprpr).begin(),TU) # define FOR(i,tptpt,ypypy) for(LL i=(tptpt);i<(ypypy);i++) # define REP(i,upupu) FOR(i,0,upupu) # define INIT std::ios::sync_with_stdio(false);std::cin.tie(0) const int mod = 1e9 + 7; string s; int dp[10101]; //sの部分文字列同士の比較がO(1)でできるもの //https://topcoder.g.hatena.ne.jp/spaghetti_source/20130209/1360403866 const ULL MOD = 1000000007ULL; struct rolling_hash{ int n; vector t, h; rolling_hash(string s){ n = (int)s.size(); t.assign(n + 1, 0); h.assign(n + 1, 0); t[0] = 1; for(int i = 0;i < n;i++)t[i + 1] = t[i] * MOD; for(int i = 0;i < n;i++)h[i + 1] = h[i] * MOD + s[i]; } //[l, r)(もとの文字列の0-indexed)のハッシュ値を返す ULL hash(int l,int r){ if(l > r)return 0; return h[r] - h[l]*t[r - l]; } }; int main(){ INIT; cin >> s; s = ' ' + s; rolling_hash r(s); dp[0] = 1; for(int i = 1;i <= ((int)s.size() - 1)/2;i++){ for(int j = 1;j <= i;j++){ if(r.hash(j, i + 1) == r.hash((int)s.size() - i, (int)s.size() - j + 1))(dp[i] += dp[j - 1]) %= mod; } } int ans = 0; REP(i, (int)s.size()/2 + 1){ (ans += dp[i]) %= mod; } cout << ans << endl; }