#include<iostream>#include<cstdio>#include<string>using namespace std;int main(){    string s;    cin >> s;    int i;    for(i = 0;i < s.size() && s[i] == ‘a‘;i++);    if(i == s.size())   s[i-1] = ‘z‘;    else    {        for(;i < s.size() && s[i] != ‘a‘;i++)   s[i] = s[i]-1;    }    cout << s << endl;    return 0;}