#include <bits/stdc++.h>
using namespace std;

int main() {
  string S;
  cin >> S;
  for (int i = 0; i < S.size(); i++) {
    int tmp = S.at(i) - 'A';
    tmp -= i + 1;
    while (tmp < 0) tmp += 26;
    S.at(i) = 'A' + tmp;
  }
  cout << S << "\n";
}