백준 2675

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

// Press Shift twice to open the Search Everywhere dialog and type show whitespaces,
// then press Enter. You can now see whitespace characters in your code.
public class Main {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
StringBuilder sb = new StringBuilder();

    int a = Integer.parseInt(br.readLine());

    for (int i = 0; i < a; i++) {
        StringTokenizer st = new StringTokenizer(br.readLine());

        int x = Integer.parseInt(st.nextToken());

        String text = st.nextToken();

        for (int j = 0; j < text.length(); j++) {
            char ch = text.charAt(j);
            for (int k = 0; k < x; k++) {
                System.out.print(ch);
            }
          
        }
        System.out.println();

    }









}

}