#include using namespace std; //#define int long long #define rep(i,n) for(int i=0;i<(n);i++) #define reps(i,f,n) for(int i=(f);i<(n);i++) #define pb push_back #define all(v) (v).begin(),(v).end() typedef vectorvint; typedef pairpint; typedef vectorvpint; signed main(){ string s;cin>>s; setst; int n=s.size(); rep(i,1<>j&1)t+=s[a++]; else t+=s[b--]; } st.insert(t); } cout<