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--; } } }