#include <vector>
#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T>
ostream_iterator<T> oit(const string &s = " "){ return ostream_iterator<T>(cout,s.c_str()); }
inline auto rep(int l, int r) { return views::iota(min(l, r), r); }
inline auto rep(int n) { return rep(0, n); }
inline auto rep1(int l, int r) { return rep(l, r + 1); }
inline auto rep1(int n) { return rep(1, n + 1); }
inline auto per(int l, int r) { return rep(l, r) | views::reverse; }
inline auto per(int n) { return per(0, n); }
inline auto per1(int l, int r) { return per(l, r + 1); }
inline auto per1(int n) { return per(1, n + 1); }
#define A(a) begin(a),end(a)
inline auto len = ranges::ssize;

struct chash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};
template<typename T, typename U> using pb_map = gp_hash_table<T, U, chash>;
template<typename T> using pb_set = gp_hash_table<T, null_type, chash>;
#define K first
#define V second

using ll = long long;
using ld = long double;

using vi = vector<int>;
using vii = vector<vector<int>>;
typedef vector<ll> vll;
using pll = pair<ll,ll>;
using pii = pair<int,int>;


constexpr int N = 8;
using DECK = array<int,N+1>; //14th one is a bitmask, :holyfuck:
map<DECK,ld> dp;

string s;

char mp[256];

ld rec(DECK d){
    if(d.back()==0) return 0;
    if(dp.contains(d)) return dp[d];
    int sm = accumulate(d.begin(),d.end()-1,0);
    // ranges::copy(d,oit<int>()),cout<<endl;
    ld &state = dp[d];

    for(int i=0;i<N;i++){
        if(!d[i]) continue;
        ld p = d[i]/((ld)sm);
        d[i]--;

        int old_mask = d.back(),cur=i;
        while(cur<7 and d.back()&(1<<cur)){
            d.back()^=(1<<cur);
            cur=mp[s[cur]];
        }
        state += p*(rec(d)+1);

        d[i]++;
        d.back()=old_mask;
    }

    return state;
}

void run()
{
    cin >> s;
    DECK d{0};
    d.back() = (1<<7)-1;
    for(int i : rep(7)){
        d[i]=4;
    }
    d[7] = 52 - 4*7;

    for(char c : s){
        int idx = mp[c];
        if(idx<7) d[idx]--;
        else d[7]--;
    }
    auto ans = rec(d);

    cout << fixed << setprecision(10) << ans << '\n';
}

int main()
{
    //KING OF THE WORLD...... U.W.T.B
    cin.tie(0);
    ios_base::sync_with_stdio(false);

    string cards{"A23456789TJQK"};
    for(int i : rep(len(cards))) mp[cards[i]]=i;

    run();
}