#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <algorithm>
#include <numeric>
#include <functional>
#include <set>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cctype>
#include <climits>

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define FOE(i,a) for(auto i : a)
#define ALL(c) (c).begin(), (c).end()
#define EXIST(v, n) (std::find(v.begin(), v.end(), 1) != v.end())

using namespace std;

int main(int argc, char *argv[]) {
    string s, ans;
    cin >> s;
    REP(i, s.size()) {
        int n = (s[i] - 'A' - i - 1) % 26;
        if (n >= 0) {
            ans += n + 'A';
        }
        else {
            ans += 'Z' + 1 + n;
        }
    }
    cout << ans << endl;
}