#include <bits/stdc++.h>
using ll = long long;
using llu = long long unsigned;

using namespace std;

int main() {
    string S;
    cin >> S;
    char c = S[0];
    switch (c) {
        case 'A':
        case 'C':
        case 'D':
        case 'F':
        case 'G':
            S+="#";
            break;
        case 'B':
            S = "C";
            break;
        case 'E':
            S = "F";
            break;
    }
    cout << S << endl;
    return 0;
}