#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
using ll = long long;
using namespace std;
const int INF = 1e9;

int main() {
    string s;
    cin >> s;

    rep(i, s.size()) {
        int now = s[i] - 'A';
        now += 26 * 100;
        now -= i + 1;
        cout << char(now % 26 + 'A');
    }
    cout << endl;

    return 0;
}