#include <bits/stdc++.h>
const int Maxn = 100005;
using namespace std;
char s[Maxn];
int l, r;
bool flag = 0;
int main() {
  scanf("%s", s);
  int len = strlen(s);
  for (int i = 0; i < len; i++) {
    if (s[i] == 'a') {
      if (flag == 1) break;
      r = ++l;
      continue;
    }
    flag = 1;
    r++;
  }
  for (int i = l; i < r; i++) s[i] = s[i] - 1;
  if (l == r) s[l - 1] = 'z';
  for (int i = 0; i < len; i++) printf("%c", s[i]);
}
