import java.util.Scanner;

public class MagicWrd {
    public static void main(String args[]) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
         int primes[]= {67,71,73,79,83,89};
        int counter=0;
        int primes1[]={97,101,103,107,109,113};
        while(counter<n)
        {
            int length=sc.nextInt();
            String s1=sc.nextLine();
            String s=sc.nextLine();
            outer:
            for(int x=0;x<length;x++)
            {
                int c=s.charAt(x);
                int min=500;
                int diff=0;
                if(c>=0&&c<=90)
                {
                for(int y=0;y<6;y++)
                {
                    if(c==primes[y])
                    {

                    System.out.print((char)c);
                    continue outer;}
                    diff=c>primes[y]?c-primes[y]:primes[y]-c;
                    if(diff<min)
                    {
                        min=diff;
                    }
                }

                int top=c+min;
                int bottom=c-min;
                if(bottom==67||bottom==71||bottom==73||bottom==79||bottom==83||bottom==89)
                {
                    System.out.print((char)bottom);
                }else
                System.out.print((char)top);
            }
            else
            {
                for(int y=0;y<6;y++)
                {
                    if(c==primes1[y])
                    {

                    System.out.print((char)c);
                    continue outer;}
                    diff=c>primes1[y]?c-primes1[y]:primes1[y]-c;
                    if(diff<min)
                    {
                        min=diff;
                    }
                }

                int top=c+min;
                int bottom=c-min;
                if(bottom==97||bottom==101||bottom==103||bottom==107||bottom==109||bottom==113)
                {
                    System.out.print((char)bottom);
                }else
                System.out.print((char)top);

            }
           continue;
        }

            counter=counter+1;
            System.out.println();

        }







    }}