#include <iostream> #include <string> #include <set> using namespace std; void dfs(string s, const string &r, int b, int e, set<string> &result) { if (b == e) { result.insert(s); return; } dfs(s + r[b], r, b + 1, e, result); dfs(s + r[e - 1], r, b, e - 1, result); } int main() { string S; cin >> S; set<string> result; dfs("", S, 0, S.length(), result); cout << result.size() << endl; }