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