> import java.io.*;
> import java.util.*;
> 
> public class Main {
>   public static void main(String args[]) throws IOException {
>     BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
>     int light[] = new int[1001];
>     String ch = new String();
>     int a, b;
>     String str = new String();
>     int n = Integer.parseInt(br.readLine());
>     while(n-- >= 0) {
>       int t = Integer.parseInt(br.readLine());
>       for(int s = 0; s < 1001; s++)
>           light[s] = 0;
>       while(t-- > 0) {
>         str = br.readLine();
>         StringTokenizer st = new StringTokenizer(str);
>         ch = st.nextToken();
>         a = Integer.parseInt(st.nextToken());
>         b = Integer.parseInt(st.nextToken());
>         for(int i = a; i < b; i++)
>           light[i]++;
>       }
>       for(int j = 0; j < 1001; j++)
>       {
>         if(light[j] != 0)
>           System.out.print(""+(char)('@'+light[j]));
>           System.out.flush();
>       }
> 
>       System.out.println("");
>       n--;
>     }
>   }
> }