#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int st = 0;
  while (st < s.size() && s[st] == 'a') {
    ++st;
  }
  int fin = st + 1;
  while (fin < s.size() && s[fin] != 'a') {
    ++fin;
  }
  for (int i = st; i < fin; ++i) {
    s[i] = 'a' + (s[i] - 'a' + 25) % 26;
  }
  if (st == s.size()) {
    s[s.size() - 1] = 'z';
  }
  cout << s << endl;
  return 0;
}
