import java.util.*;

public class CompareString
{
    public static void main(String[] args)
    {
        while (true)        
        {
            Scanner in = new Scanner(System.in);   
            char[] input=in.next().toCharArray();   
            StringBuffer output=new StringBuffer();
            int num=0;
            for(char ch:input)       //这一句是什么意思呢？？？？？？？？？？？？？？？？？？？？？？？？
            {

                if(Character.isUpperCase(ch))      
                {
                    num=ch-'A'+27;
                }
                else
                {
                    num=ch-'a'+1;
                }
                num=(num*num+num+1)%52;
                if(num>26)
                {
                    output.append((char) (num-27+65));   
                }
                else
                {
                    output.append((char) (num+97-1));
                }
            }
            System.out.println(output.toString());  //output已经是字符串了，为什么还要用toString转化成字符串呢？？？？？？？？？？？？？？？？
        }
    }
}


求大神们解答，不甚感激