#include "bits/stdc++.h" using namespace std; #define int long long #define FOR(i, a, b) for(int i=(a);i<(b);i++) #define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--) #define REP(i, n) for(int i=0; i<(n); i++) #define RREP(i, n) for(int i=(n-1); i>=0; i--) #define ALL(a) (a).begin(),(a).end() #define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end()); #define CONTAIN(a, b) find(ALL(a), (b)) != (a).end() #define array2(type, x, y) array, x> #define vector2(type) vector > #define out(...) printf(__VA_ARGS__) int dxy[] = {0, 1, 0, -1, 0}; void solve(); signed main() { #if DEBUG std::ifstream in("input.txt"); std::cin.rdbuf(in.rdbuf()); #endif cin.tie(0); ios::sync_with_stdio(false); solve(); return 0; } /*================================*/ int N,M,Q; template class ST { using F = function; int size; T init; F f; vector seg; int depth = 0; public: ST(int size, T init, F f): size(size), init(init), f(f) { while (1<>=1) seg[k] = f(seg[2*k], seg[2*k+1]); } T query(int a, int b) { a += 1<>= 1; b >>= 1; } return f(l, r); } T operator[] (int k) { return seg[k + (1<(10, 0, [](int a,int b){return a+b;}); // l~rまでで回文になるかどうか bool check(int l, int r) { bool ok = true; while(l>S; N = S.size(); REP(i,N) seg->update(i, check(i,N-1)); // REP(i,N) out("%lld: %lld\n", i, (*seg)[i]); int ans = 0; REP(i,N-3) if(check(0,i)) { FOR(j,i+1,N-2) if (check(i+1, j)) { ans += seg->query(j+2, N); } } cout << ans << endl; }