#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using P = pair<int, int>;
const int INF = INT_MAX;
const ll LINF = LLONG_MAX;
#define rep(i, s, n) for (int i = (s); i < (int)(n); ++i)
#define repl(i, s, n) for (ll i = (s); i < (ll)(n); ++i)
#define repr(i, s, n) for (int i = (s)-1; i >= (int)(n); --i)
#define vec(type,name,size) vector<type>name(size)
#define vecini(type,name,size,ini) vector<type>name(size,ini)
#define vv(type,name,h,w) vector<vector<type>>name(h,vector<type>(w))
#define vvini(type,name,h,w,ini) vector<vector<type>>name(h,vector<type>(w,ini))
#define all(x) (x).begin(),(x).end()
#define allr(x) (x).rbegin(),(x).rend()
#define sz(x) ((int)(x).size())
template<class T> bool chmin(T& a, T b){ if(a > b) { a = b; return true; } return false; }
template<class T> bool chmax(T& a, T b){ if(a < b) { a = b; return true; } return false; }

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  
  string s; cin >> s;
  if(s == "A" || s == "C" || s == "D" || s == "F" || s == "G") s += '#';
  else if(s == "E") s = 'F';
  else if(s == "B") s = 'C';
  cout << s << endl;
  return 0;
}