#include <bits/stdc++.h>
using namespace std;
#define repi(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define rep(i,n) repi(i,0,n)

string s;

string solve() {
    rep(i,s.size()) s[i] = (s[i]-66-i+26)%26+65;
    return s;
}

void input() {
    cin >> s;
}

int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    cout << fixed << setprecision(12);
    input();
    cout << solve() << endl;
    return 0;
}