#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); ++i)

int main() {
  string s;
  cin >> s;
  rep(i, s.size()) {
    int z = s[i] - 'A';
    z = (z - i - 1 + 26 * 1000) % 26;
    cout << (char) ('A' + z);
  }
  cout << endl;
  return 0;
}