import java.util.*;

public class Main{
    public static void main(String[] args){
        
        Scanner sc = new Scanner(System.in);
        
        String s = sc.nextLine();
        
        char[] ch = new char[s.length()];
        
        int minus;
        
        for(int i = 0; i < s.length(); i++ ){
            
            minus = i + 1;
            while(minus < 26)
                minus = minus - 26;
            
           int j = s.charAt(i) - minus;
           ch[i] = (char) j;
           
        }
        
        System.out.println(new String(ch));
        
    }
}