import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int t = in.nextInt();
        while(t>0){
            int n = in.nextInt();
            in.nextLine();
            String str = in.nextLine();
            char[] ch = str.toCharArray();
            for(int i=n-1;i>=0;i--){
                System.out.print(ch[i]);
            }
            System.out.println();
            t--;
        }
        
    }
}