#include <bits/stdc++.h>
using namespace std;
char a[100001];
int main() {
  scanf("%s", a);
  int len = strlen(a);
  int start = -1, end = len - 1;
  for (int i = 0; i < len; i++) {
    if (a[i] == 'a') {
      if (start != -1) {
        end = i - 1;
        break;
      }
      continue;
    }
    if (start == -1) start = i;
  }
  if (start == -1) {
    a[len - 1] = 'z';
  } else {
    while (start <= end) {
      a[start]--;
      if (a[start] < 'a') a[start] = 'z';
      start++;
    }
  }
  puts(a);
  return 0;
}
