#include <bits/stdc++.h>

using namespace std;

#define REP(i, n) for(int i = 0; i < n; i++)

int main() {
    string s;
    cin >> s;
    REP(i, s.size()) {
        int j = i + 1;
        s[i] -= j % 26;
        cout << (char) ((s[i] >= 'A') ? s[i] : (s[i] + 26));
    }
    return 0;
}