import java.util.*;
import java.lang.*;
import java.io.*;

// The main method must be in a class named "Main".
class Main {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        String value=sc.next();
        String result="";
        for(int i=0;i<value.length();i++)
        {
            Character ch=value.charAt(i);
                if(value.charAt(i)!='a' && value.charAt(i)!='A')
                {
                    result=result+(char)(ch-1);
                }
               else{
                    result=result+"z";
                }
        }
        System.out.println(result);
    }
}