#include <iostream>

using namespace std;

int main()
{
    string s;
    cin >> s;
    if (s.size() < 3) {
        cout << "NO";
        return 0;
    }
    if (s[s.size() - 2] != 'X') {
        cout << "NO";
        return 0;
    }
    if (s[0] != 'A' || s[1] != 'B') {
        cout << "NO";
        return 0;
    }
    for (int i = 2; i < s.size() - 2; i++) {
        if (s[i] != 'C') {
            cout << "NO";
            return 0;
        }
        if (s[i + 1] == 'E') {
            i++;
            continue;
        }
        if (s[i + 1] == 'D' && s[i + 2] == 'F') {
            i += 2;
            continue;
        }
        cout << "NO";
        return 0;
    }
    cout << "YES";
    return 0;
}