#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
    string s;
    
    cin >> s;
    
    char carr[s.length()];
    
    s.copy(carr, s.length());
    
    for (int i = 0; i < s.length(); i++) {
        int sub = (i + 1) % 26;
        int c = carr[i] - sub;
        if (c < 65) {
            carr[i] = 90 - (64 - c);
        } else {
            carr[i] = c;
        }
    }
    
    carr[s.length()] = '\0';
    cout << carr << endl;
    
    return 0;
}