#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  string s;
  cin >> s;
  int i = 0;
  string str = "";
  if (s.size() == 1) {
    if (s[0] == 'a')
      cout << 'z' << endl;
    else
      cout << char(s[0] - 1) << endl;
    return 0;
  }
  while (s[i] == 'a' && i < s.size()) i++;
  if (i == s.size()) {
    for (int l = 0; l < s.size() - 1; l++) cout << 'a';
    cout << 'z' << endl;
    return 0;
  }
  for (; i < s.size(); i++) {
    if (s[i] != 'a')
      str += s[i];
    else
      break;
  }
  for (int j = 0; j < str.size(); j++) {
    if (str[j] == 'a')
      str[j] = 'z';
    else
      str[j] = char(str[j] - 1);
  }
  for (; i < s.size(); i++) str += s[i];
  reverse(str.begin(), str.end());
  while (str.size() < s.size()) {
    str += 'a';
  }
  reverse(str.begin(), str.end());
  cout << str << endl;
  return 0;
}
